Shad,
Here are my answers to some of your questions.
How should I rebuild it? stock specs?, possibly forged pistons?, better head gasket? Different cam?
Would I benefit by running a OFFY intake?
Would you get a HEI and lock it out?
Bore it the minimum needed.
Get forged, turbo type pistons.
Use a Felpro 1025 head gasket and ARP head studs.
There are lots of cam choices. Small RV style will work good, but custom ground cams are available.
A offy intake would help, but a Clifford would help more.
Rework the head. Minimum 1.84/ 1.6 valves and port the head. Lumps will also help.
Use a rebuilt HEI with working timing, devise a vac can to pull timing when under boost and apply timing when in vac.
