I have a 1966 283 sbc in a Chevelle Malibu. It runs great, does not smoke, and has great compression. While I was replacing the old parts on the engine including: hei distributor, intake, carb, cam, lifters, push rods, rocker arms, and headers. Before I installed I started the car stock. No oil leaked from anywhere. I have a timing cover leak from the one I put on but I will shortly be replacing it. After I would drive the car and park after the parts were installed. I would notice a small puddle of oil. I was wondering if anyone knows what this could be? I don't know if it is the oil pan gasket or rear main seal. I honestly do not know. Any suggestions would be greatly appreciated.