Ok. Issues with timing. No dial gauge available. First, gapped the points to .015 per Clymers. Then wired the advancer weights fully out. Stuck a pencil in the spark plug hole and used a mm ruler to find TDC. Turned cam clockwise (BTDC) for just under 2mm (1.8 called for in book). The points are touching all the way through the adjustable area of the points, so the spark is going way to early. By continuing to turn the cam, it looks like the spark is firing about 1/2 - 3/4 inch before TDC. It backfires then runs backwards for a short time. I need help. It's almost like the cam is 180 degrees off. I have adjusted the points plate all the way through the available slide space.