2005 G35 coupe here. I removed the W brace and installed an aftermarket one. I believe its from FRF racing. Maybe FDF racing. Not sure.... anyway, i removed this piece because it was rusted as hell.... and the part it bolts into is also rusted. What part is this? I need to replace it!

 

Here's a pic I found elsewhere on the site.

 

Those pieces at the ends of the "W" are called "rear member stay"

 

any idea how many bolts and how many nuts attach this piece to the car? seems like 1 nut and 4 bolts each. and thank you sir

 

This might help.