The O-ring is around the outside of the outer extended ring and is visible in the pic as a black ring. It's used to keep dust and moisture from getting into the distributor cap and causing shorts. Look carefully at the pic.

__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.