Working at an AMC dealership I never heard of a "#% fouling" problem, but there were a few years when the 232 needed to be driven like you stole it, fresh off the lot, to get the chrome rings to seat. A tablespoon of BonAmi scouring pouder sifted into the intake at 2000 RPM solved that problem.
They also ran the oil for the rockers up around one of the headbolts, and if you didn't change the oil regularly that passage would coke up, starving the rocker arms of oil. They'd chirp pretty good untill you either managed to flush the passage, or removed the head bolt andcleaned things up. I ended up putting an external oil line on my '65 beater to solve the problem.