What to look for in a 1964 C30?

[billye1982]

So I am going to look at a 1964 Chevy C30 tonight that will be the main part of my EVENTUAL crew cab dually. Are there any hidden areas that are know to be rusted out? I know I have a HUGE project ahead of me, so replacing a few rusted areas will be pretty small in the whole scope of the project, I just don't want to buy it just for a dually roller. It has a flat bed (that will come off, I will make a bed with fender flares), a V8 and a floor shift. The person who has it does not know much about it.