I just purchased a 1968 Pontiac Firebird. The main reason I bought it was that it was 98% rust free, all Original panels, floors are rock solid, it's been in dry storage since 1994 and before that spent its life under a car port. The reason I could afford it was the one repaint that was done in 94 was done horribly, all of the seals, etc are dried out, and it's a base 250 six car.

Supposedly the motor was rebuilt recently, including a bore and new pistons. The guy I bought it from couldn't get it running right and it runs like crap - part of the reason being the single barrel is pouring gas from everywhere and it appears to be missing at least one vacuum line (PCV?) but I can't seem to find jack squat on parts or resource material for these motors other than some online pics of pretty looking motors. Simple crap like firing order and buying a fuel pump and new motor mounts.

Where can I find an online source or book on how to work on/tune one of these motors and what parts cross over with the Chevrolet sixes?

I'm not a complete idiot. I have a 65 Mustang with a very good running 302 and a 1967 C10 with a 350. Very familiar with V-8s and their set-ups. A little clueless here. I'd hate to toss a good motor (compression test soon), but if I can't find crap for it, I have a Pontiac 400 that can go in it's place.