I wanted to know if there was a way to turn my awd gs350 into rwd only by pulling a fuse or something, like it is for the Infiniti g35

 

Not possible on the GS/IS. The Infiniti uses a "hybrid" mechanical/electronic system that can divert all the power to the rear instead of the static 30/70 on the GS/IS.

 

I believe theres a tiny driveshaft from the transmission, to the front diff. Maybe you can just remove that!

I am curious to know if it will trip up awd warnings, but if you just remove that driveshaft, the front wheels will still spin and the speed sensors, because there in the hubs still register speed. Give it a shot! But before you remove the driveshaft with a permanent marker, put reference points on the driveshaft and flanges. So when you reinstall them you place them back in there original location, to help avoid vibrations later on.

 

the infiniti AWD SYSTEM is crap worst one made , my niece has a 2014 infiniti whitch has error codes ,when your on the highway you have to pull over let the transfer case oil cool then restart ,if your tires are low on tread it overheats the transfer case oil JUNK....THE LEXUS AWD SYSTEM IS TROUBLE FREE...just buy a cheap 2007-2008 rear wheal drive gs460 than mess with a perfect car...your choice