Torque wrenches and 40 year-old head bolts
 

I figured out that 72-FLB's was not enough to seal the head gasket on the Roadrunner PUP.
I ran the engine for 25 minutes 1st start after rebuild- overheat, RED.
Ran again after it cooled...same thing.

Next day, pulled valve cover off. Engine cool and retightened head bolts to 80-FLB's.
Engine running a little cooler but still a liittle too much.
Let cool.
Next day, pulled valve cover and retightened head bolts to 85FLB's.

Much better Now running about normal. No over heat.

Cleaned out RAD with Drano and flushed with boiling hot water! Clean as a whistle!.