I would.Beautiful GTO!
I was going to go with 15 X 8 rear rims.
The only reason I have 15x7's is because at first I put 2456015s all the way around. Then I did my disc brake conversion, which widened my track by about 3/16" causing the fronts to rub. So I dropped to 2356015. Then I put a 12 bolt in with 3:31's and since now I didn't have the 4 the same size look I wanted, I went with the biggest I could on the back.