Hi !

My comment:
"To overhaul the Topend helps only to reduce the misfire problem in the wallet from the mechanic but not your engine".
;-)


Your steps from the trouble shooting where good and logical :shake:
After changing the parts (points, spark plugs, coil), swapping the HT wires and checking the compresion (all cylinder are good) it is logical that the problem is the distributor cap and finger.
Change the finger only because it is better to change it together with the cap (my experience).
You inspected and cleaned it but sometimes you cant see micro cracks in the plastik and this very thin cracks can cause the the spark spark went somewhere (to negative ground).
Please report if that was the problem, thank you.

Regards
Ruediger