All good advice but this old "Stovebolt six" has both intake and exhaust manifold in one piece so the torque has to be either or. Also, the whole thing is cast iron.To make things a little more hairy, there is no way to get the head of a torque wrench down between the ports. The nuts on each end are brass and I expect they would strip before the steel bolts.
I must have done it right because the engine runs smooth, 22 pounds of vacuum and no leaks.

Anyway, I came across a catalog of old Chevy parts in Georgia, and I just ordered a shop manual.