Years ago GM had a service bulletin out that said a miss at constant speed light throttle was caused by a bad bearing in the distributor allowing the shaft to wobble the cure was to replace the bearing and the permanent cure was to install an extra bushing while you had the distributor apart. These bushing used to be about a dollar each. I don't even know if they are still available. They discovered this problem in the early 70's six cyl trucks and it seem to be worse in standard shift vehicles. My 69 chev 1/2 ton did it and I installed the dble bushing and it ran better than new.
Thanks for the suggestion. Like I said, I'm getting an HEI soon and I'll replace the parts that need replacing and keep this in mind. I'll let you guys know
