Great insights and thank you. You've been so helpful through this process. I will look for a local speed shop that can do HEI distributors. I do have vac advance as well and will explore if there is a way to limit it a bit. I've seen that before. The squeal was a belt at first, which i add some slip grease to and it quieted. I did however seem to tear up the TACH gear, as my mechanical tach is no longer functioning. Perhaps time to switch to electronic... or see if I can find the parts to rebuild it.