I would definitely replace the headgasket if it is original.

I would also plan on having the head rebuilt... I know it sounds excessive, but it will be worth it in the future. One good test is to wiggle the valves in the guides.
-set the crank to TDC
-remove the rocker arm set for the first piston
-remove the exhaust valve spring and retainer
-remove the valve stem seal
-wiggle

If you feel / or see any play... its time for a head rebuild. If you don't see any play, do this test on another piston. Rotate crank about 70 degrees and use the numbers on the valve cover to determine which piston as now at TDC.


Other than that... valve stem seals and front crank seal.

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