Very hard thing to do, finding wheels for a Vette over here in Poland that is. I found out BMW's have the same stud pattern that the Corvette has, only the hub size are actually slightly larger than a Corvette's. So i bought a hub rings to make up the difference and everything is good.
DOTZ Mugello Drk
Front 18x8 ET35
Rear 19x9.5 ET32
The ET's being so wide gives the illusion that the wheels are actually wider than they really are. Then fit perfectly on the hub and there shouldnt be any tire rubbing issues on the guards.
I didnt go wider than the more or less stock Corvette wheels because the HP in my LS1 doesnt justify it. In my opinion, the car is already considerably lighter than a Vette with the same HP so the width of these wheels should be more than enough.