which CORRECT radiator?
 

purchased a new radiator that was supposed to be correct only to find it is not. 1977 350 heavy half ton with a th-350.
If I had the original still, Id measure it to choose the right one. The one I have now is a little oversized and from what Ive come across seems to be for the big block ? Its a little too big to sit in the brackets and "fingers" by just a bit.

Any idea which radiator SHOULD be in there? Id like to get the shroud back on and the radiator mounted correctly.

Re: which CORRECT radiator?
 

Sounds like you got the upgraded 4 core radiator. There are many "correct" radiators for your year, but they can be 3 core or 4 core, shorter or taller and your fan shroud and radiator mounts will need to be specific to the radiator.

Re: which CORRECT radiator?
 

well now, that just throws a BIG OL wrench in what I thought was a little easier. How should I measure? Reinstall all my original mounting hardware minus the current radiator maybe?

Re: which CORRECT radiator?
 

Is the upper radiator mount flat from where it mounts to the core support to where it attaches to the radiator or does it drop down to attach to the radiator? This will tell you if you need a short or tall radiator