EDIT: Hit the 10k character limit, see the last post for more description and intent.

For reference, 1/4-20 means 1/4 inch threaded fastener, 1/4-20 is the common name which includes the "20 threads per inch" wording.

Hardware needed:

Bench vise or table clamp to hold material while cutting/drilling.
2x 1/4-20 toggle bolts, any length
1x Everbilt "mending plates" from Home Depot or elsewhere, found with the gate hinges and latches. This particular item has 2 of the needed holes already drilled at the proper location, literally ANY piece of metal that is 3" x 3/4" will work
Sawzall or hacksaw
Flat file
Drill with 1/4" bit, optional and preferred is a smaller bit to make a pilot hole
1/4-20 tap
#2 phillips screwdriver
Small flat blade precision screwdriver or something else to pop off the seatbelt guide bolt cover
Pencil
Tape measure

WARNING! Drilling/cutting metal throws chips, wear the appropriate eye and hand protection, cut or drilled metal will be HOT! Wait a few minutes before handling materials or use gloves, when in doubt ASK FOR HELP! Don't be dumb! Don't blame me if you screw yourself up!

The rest of this will be mostly pictures with a description ABOVE each picture:

1. Remove seatbelt guide bolt cover, insert the small flat blade screwdriver and gently pry out until it pops open. Don't just force it once it snaps and look at the next two pictures so you see exactly where it hinges and snaps at. This piece does not feel fragile and I suspect you would have to seriously be abusing it to brake anything but it's a hard to acquire item so no sense wrecking it...



Next, the distance between the bolt holes is 1_7/32" apart. I determined that I wanted to move my seat belt bracket exactly the distance between the bolts farther out because any less would require significant machine work for a working adapter bracket and any MORE would cause too much of the existing guide to protrude past the edge of the seat.




Home depot conveniently had a bracket in the hinges and latches section that matched exactly the dimensions I was looking for and even had two of the holes drilled in the correct location...



First tap one of the end holes, next mark the exact center of the plate and drill a 1/4" hole, also drill out the hole on the far end to 1/4". Clean up both sides of the plate with a file to remove the drilling burr when finished.





Next, the side with the 1/4-20 tapped hole needs to be angle cut so it doesn't protrude past the back edge of the seatbelt guide. I used a sawzall with a bi-metal blade, there are many options for cutting off this piece or if a sawzall is not available to you then you could FILE the metal off but it would take probably 5 minutes per bracket, if you do opt for the filing method, only file in one direction to prevent dulling your file, do NOT backdrag a file on any steel surface... clean up the sharp edges of the cut with a file if you do use a metal cutting blade of any kind.



Next cut down the 1/4-20 toggle bolt, I opted for a toggle bolt because it has a very large head and doesn't require the use of a washer. I think this looks cleaner overall and toggle bolts are plentiful at any hardware store. You will have to determine the length on your own, aim for as little bolt protruding past the bracket as possible, clean the threads of the bolt with the file if you used a saw because it will be a little rough and you want them smooth. One of my seatbelt guides the hole was slightly smaller and I had to ream it out with the 1/4" drill bit just a touch to make it fit. If you must drill your existing seatbelt bracket I STRONGLY RECOMMEND to use a drill with a clutch on it, those are the ones that have a numbered ring around the chuck so it will break free at a much lower torque, you don't want the drill bit to bind up and crack your plastic seatbelt guide. I set the clutch on my Makita at 3 which is a VERY light clutch setting and held the bracket in one hand while drilling.




Next, attach the seatbelt guide to the relocation plate, verify there are no (or very little) threads protruding through the plate. Optionally you could file the bolt a little flatter once it's installed in the plate.



Now reinstall the seatbelt guide onto the seat. In my final revision bracket I intend to machine a piece that will more adequately fill the existing spot on the seat where the bracket used to fit as well as protruding to the end of the seatbelt bracket with a contour that fills the gap between the seat and the outer edge of the bracket. This will require quite a bit of time in CAD and writing a cut for a CAD mill, since those things aren't generally available to folks I'm going to leave it up to the user to determine how they would modify to fill those gaps as needed or simply leave them be since it's only visible from very EXACT angles and once the seatbelt is installed in the guide it completely hides the protruding metal bracket anyways...





Reinstall the snap-on bolt cover and put the seatbelt back in the guide, as you can see once the seatbelt is back in the guide it covers up the protruding bracket nicely. Therefor the revision 1 bracket is perfectly serviceable with a little coat of paint to match the leather.




Before, the seatbelt is obviously riding on my neck, I would be CONSTANTLY tugging it down to keep it closer to my shoulder.



After, the seatbelt is not touching my neck and naturally rides much closer to my shoulder, it's still CLOSE to the neck for my 5'2" wife but she said it's infinitely more comfortable than where it sit before which was almost touching her chin...




I wouldn't normally endorse modifying the restraint system of a vehicle but since the G35 coupe poses an obvious risk to occupants due to negligent design I have no qualms about suggesting this modification for any other users suffering from the same problem. In the event of a powerful accident the seat belt guide will likely be damaged but it should keep the seatbelt in a safer position on the occupant than where it sits normally.

Post any questions below, I'll try to answer them when I have time.

 

EDIT: Moved from beginning of first post due to 10,000 character restriction

Anyone who is in the 5'9" range with a 2006-era coupe probably knows how the seatbelt hits you in the neck and not at the shoulder like it should. Ironically the seatbelt guide is designed for someone 6' or taller but the interior dimensions are so cramped that a person of such height brushes their head on the roof...

This thread is designed as a guide or direction for someone who wishes to modify the seatbelt guide and not necessarily a final fit and polished piece. My intention is for this item to essentially be a revision 1 item that will go through a second design and iteration process to determine the best way to cover the existing seatbelt guide location by matching the contour of the seatbelt guide and creating a better fitting template in the future, match painted for the seat leather color so it all blends together. However the second revision will happen at a later date because I'm still recovering from distal bicep tendon surgery and performed all the work herein with only one arm... in 4 months when I have the use of BOTH arms I will be able to properly use a bandsaw, jigsaw, drill press, etc and I'll try to remember to update this thread with a better template for others to use as a reference.

Using the exact pieces I did this entire process took me about 15 minutes to relocate BOTH seat belt guides and cost me approximately $5 plus tax so for someone looking to do this on a budget and who doesn't mind the ugliness of a square cut piece of galvanized steel (you should at least make an attempt to paint it with a semi-matching color) the revision 1 bracket would work just fine.

So to backtrack a touch, my seatbelt hits me in the neck when I'm driving. I'm 5'9" tall and this is SUPER annoying to me, my wife is 5'2" and it's even worse, she hated riding in the passenger seat because of that damned seatbelt so she would usually ride in the back and make our son sit in the passenger seat so he could get seatbelt neck marks. From a safety perspective this is also very dangerous in the event of a frontal collision, heck even the owners manual says to have the seatbelt hit you in the shoulder but unless you are very tall this is not possible with the OEM equipment! I've tried seatbelt clips similar to the ones used for car seats, they dig into your belly. I've tried seatbelt extenders, they sort of work but then you end up with a second belt buckle to fiddle with and they also dig into your belly. I've tried the nylon fastener/covers that go just above the buckle, they twist the belt at an awkward angle and it keeps trying to flip the shoulder belt over. I finally realized the proper way to tackle the issue is to relocate the shoulder bracket itself.

 

Can't you just swap to the 03-05 seat belt guide?

 

Neat, I'll try this with M6 bolts later this week.

 

I've been suffering in silence all these years, why didn't I try this earlier? Might make this an upcoming project.

 

I don't think the earlier coupe seat even have a seatbelt guide. The seatbelt mounting location on the pillar was slightly different and it simply rolled around the edge of the seat, one of the complaints about the early coupes was how much of a pain it is to reach the seatbelt so for the later coupes they added the seatbelt guide to keep it attached to the seat and relocated the pillar mount slightly. Here is a picture of the early coupe system.

 

Funny you should mention that. Its one of my very few complaints so far after driving the 04 for the last couple weeks. Literally have to turn my entire upper body to go look for it.

 

It's settled then, I'll be doing the cleric mod.

 

After using this for a couple weeks now I can absolutely say this was the best non-performance mod I've done on this car and highly recommend it for everyone with the same problem.

 

Plan on doing this next weekend. Picking up the hardware today actually.