An honest bit of advice-
The value of the engine is hurting due to the 2bll intake and heads. J casting heads are a dime a dozen off any early 360 (been there and done that myself) as well as the unknown cam selection.
From my perspective, I just see a shortblock with unknown internals (what compression ratio or pistons are in it? Was the block decked? How about line bore? Floating pins or pressed pins? Does it even have a windage tray?
No exhaust manifolds lowers the value even more. If you can get some answers to some of the above questions above it might help your sale.