A/FX Comet clone

I just bought a 64 comet for one of my sons and was looking for some input on what size wheel/tire we can get under it. I suggested we mini tub it but he does not want to alter the floor pans. Probably end up moving the leaf springs inboard, adding rollbar and notching shock towers for header clearance & possibly cleveland or BB later on.
Thanks,
Sheldon G.

I own a pro street 64 but cut mine up, you can go to Comet East Car Club there is fx/er's on there that can give you wheel and tire combo and like this site are very helpfull. Hope this help's