I don't know about the swap details, guess you gotta work that one out by investigation or with other's help. There's a few common bolt positions between BBC and Pontiac...?

Having things "fall out of the sky" sometimes...or maybe that's what we call it...is how things happen for someone ready to get things done. The "I can't do it/afford it" story is for the other guys you just left behind.

Shifter, is stock OK? Hacking the trans tunnel, yep now you're getting into it. Happily, "A" bodies aren't as sensitive to mods there, with their full-frame scheme. Watch out for the floorpan crossmember, if you cut it you have to make up for it.. There's a guy on E-Bay who mods tailshaft housings for a mech. speedo. Clutch, you're going to have to buy pedals and convert to hydraulic, I bet our favorite B.S. sponsor (American Powertrain) could help or you might like to figure it out. Driveshaft, easy when there are shops to help. Leave it for the last thing so you get the dimension right.

Yeah you're on the right track if this is what you want, Hat's off for having the nerve to get into it, you'll be rewarded, eventually.