I am in the process of building a 68 RS from the ground up. I purchased a stock distributor and installed a Pertonix unit to do away with the points, etc. While I had the distributor apart I freshened it up with a new bearing, a general cleaning and new bushings and springs for the centrifigal advance. Vacuum advance checks out OK. The car runs like crap! It seems like the timing is running late but it won't run with less than 45 degrees base timing. Engine vacuum is poor. I have double and triple checked to make sure the distributor is in correctly, firing order is OK. Any thoughts?