69 Camaro exhaust advice

[bearcat]

I have 355/19 on the back with a stock fuel tank. The 3" exhaust is too tight to fit between the tank and the tires. Looking for advice as to how to fix this with regards to performance and noise. I think even 2.5" will still be a little snug. Not sure if cutting the exhaust off aft of the mufflers is an idea. 468BB with 13:1 pistons and approx 600hp. 2" headers (stainless works)

Any info appreciated.