Need help identifying parts on my new addition

[bridfi]

Hello, I am new to the site and looking for some information on a truck i purchased (saved) a few months ago. While getting all my plans together for it and disassembling at the same time, im not having much luck with identifying what year and what truck certain parts came from (im told motor mounts and other things vary after 82 and 86, etc.). The cab is from a 73 c10 6-cyl but the frame has a different vin, the only thing i can find on the frame is "C67103705" which im thinking means its also a 2wd but if im not mistaken the last numbers are supposed to match the cab and they dont. The front differential is a chevy 10 bolt, rear is 14 bolt, which i think came off the K20 (3/4 TON)? It also has a 454, th350 (i know, they were never offered like this), and np203.

I only want to buy the parts for this thing once so im trying to find out what year ball joints, what year motor mounts do i buy, etc. How can i find what year the suspension parts are from? Does this frame and undercarriage setup make sense at all to anyone? Thanks for your time!