So I got this 52 GMC truck that was all apart when I got it. The firewall has a ton of holes in it. I'm working on the cab, I'd like to know which holes are supposed to be in there so I can weld up the ones that aren't supposed to be there. Also the accelerator pedal pin is rusted in. The pin should slide out from right to left , correct? Trying to understand what holds it in place other than a single cotter pin. Paul