THANKS
Overall condition is...pretty old -- 22 yrs. A little rust at gasket w/
exhaust elbows. Both sides. Definite rust on inside @ water pump and
thermostat housing. Runs smooth tho and sounds OK

So far, oil still looks good but don't know if that's something that
could just go all of a sudden...How am I certain of outside-only leak
and whether or not leaking back into the exhaust and possibly into the
cylinder ?

STB