Need help with motor numbers

[TXRookie]

I just pulled the motor out of my 68 C10 and I'm trying to figure out if its worth keeping or selling it, and buying a crate motor. I did some searching last night and figured out its a 350. But I can't figure out what the other numbers mean. I overheated the motor for the second time and it needs at a minimum a new headgasket. Not to mention I havent figured out why its overheating. Just trying to figure out what I have so I can get an idea of what its worth. ITs a complete motor from carb to to starter minus distributor. Anyway, I found the following numbers on the block.

3970010
V1207TM
04F368299

Any help would be appreciated.