how much hp and tq till...........?

[okyankee]

i have to box my 67 chevy swb frame? i got a 588ci engine in the works and want to know if i should box my frame and or roll cage it before hand. i need to replace the rear end to handle it, so i was wondering since i will make it shorter, how wide of a wheel and tire combo could i fit back there without chopping the frame. thanks for any help.