Anytime I get into fasteners like that I usually hit them with some cold galvanizing spray when everything is reassembled just to make sure when I take them off again in the future they aren't rusted up. Unfortunately cold galv is a grey color but it's on the bottom of the car so it doesn't bother me.

 

I applied some duplicolor rust barrier to the 2013 "batwing" and then applied a quart of SEM rust stop to all the frame and support problem areas. Only 2 bolts absolutely wouldn't come out even with extractors ( semetrically both on the control arm mount) so I'm running 6 bolts instead of 8 underneath. But yeah the entire original assembly came out in 3 pieces and an endless pile of rust chips.

I replaced the rear stay bar while I was at it. For anyone doing that with the tires off the ground, make sure you support your rear crossmember. Almost found out the hard way on that one.
I'm not sure if it was just my local Infiniti dealer but I got the stay bar for around $90 on sale.

 

Lol, I'm calling it the batwing from now on.

 

Yeah I thought that was funny when I found out almost every salvage yard called it that. Car-part.com is an awesome resource to find salvage yard parts for anything.

 

look on amazon ... Thats where i last seen that aftermarket part

 

how complicated is the swap? Looking at doing mine shortly as it looks like pic above. LOL.

 

Just replaced the Batwing today on my 08 G35X. Purchased from Infiniti and repainted with Spray MAX 2K Black Satin. Was easy but outermost bolts had disintegrated. Had to use a cut off wheel to create a slot to chisel those outer bolts free. I had purchased the M10-1.25x 30mm fasteners but found you actually need M10-1.25x 25mm. Had to reuse the bolts that connect to the lower control arms because 30mm were too long. Other fastener locations will accept 30mm.

It seems this part could be experiencing galvanic corrosion as it connects steel to the aluminum lower control arms.