new guy, truck rebuild.thoughts welcomed.

sup. i've got a few thing i'd like some other opinions on. first off i've just got (4 months ago) a 1972 chevy c20 flat bed 2wd 350 4 bolt main v8 it's pretty beat up and has some rust, the bed is rotted out and the engine miss fires here and there after running for more then 4 mins. my questions were 1. should i use a hard wood like cherry or black maple or get something that's pressure treated? also should i take the 350 and rebuild it from top to bottom or just take it out and put in something bigger? would something bigger cost more then just rebuilding the 350 and tuning it up?i'd like this to be my daily/ street racer. need answers!!!!