Definitely check the pipes in the center tunnel…. Make sure they not rusted through.. would be perfect time to replace them.
have a look up the paddle box and see if there’s any major wear or broken Springs (Maybe install clutch assist linkage).
brake master cylinder, clutch master cylinder.. Check hydraulic lines (Depending on preference, delete proportioning valve and shuttle valve and substitute with Wilwood brake proportioning valve) brake calipers
Check steering rack.
check the Wiring harness for 50 years of mechanic torture.
check all electrical switches
Open up Heater Core box and replace Heater Core… and valve…
Treat all the rust.
Rear uprights and wheel bearings
+ everything mentioned above
pretty much everything I did last year lol
For the “optional” stuff check out