Hi Everyone,
I have a 2003 G35 Coupe, 6MT, with brembo brakes and I was wondering how difficult would it be to change the rear rotors myself?
I really appreciate any help. Thanks forum members.

Not hard if you've done brakes before. One tip is to release the e-brake before trying to remove rotors. There's a little rubber boot you take off to get a flathead screwdriver in there to loosen the ebrake up. Otherwise you may spend a long time hammering away wondering why they won't come off.

Agreed ^ feel free to use the service manual:

http://psedog.com/cars/fsm/g35/

Make sure you have a rubber hammer to pound the rotors if they're stuck. It's a very straightforward job.