What is the biggest rubber I can run on this body?

I don't know about the later A bodies, but I got a 28 11.50 15 ET Street under my 65 Valiant. I had the MP .8" bolt on spring relocators, and SS springs in the rear. I had them mounted on 9.5" Center Line Auto Drags. I did have to roll the outer wheel lip up, but you couldn't see it. They actually fit quite well. I was surprised as all heck after I measured and re measured before I bought everything they they'd fit, but they did. I've had several A bodies, and I think......as strange as it sounds that the later cars have less room. I know that doesn't sound right, but I think that's the case.