Please help me diagnose this 273

IMHO... could be ring and/or bore wear. Your compression is up now, but there are limits to what that can tell you. If a cylinder is oiling, the compression is going to look good even with considerable wear as the oil will help seal the rings. (Now if the ring/bore wear is really bad, then then even that won't happen.)

Valve stem seals are the other typical spot and that would not be unusual in an engine that old. The valve stem seals are shot/gone. Not all that hard to replace with the engine in the car.. a very common procedure. It won't fix worn rings/bores, but it is easy enough to do that it makes sense to try.

Once you get it ti driving around, then there are observations you can make that can point you to one of these issues or the other.