Rear tires not centered in wheel well

My 68 Barracuda only has about 1/2 inch from the tire to the front of the fenderwell lip with 275/60-15`s on it. I`m with SGBarracuda, it looks like the main problem is the tire is too tall. The stock E/70-14 tires that these cars came with are probably about 24.5 inches in diameter whereas a 235/75-15 is probably around 29 inches.