The shorter the ground wire, the better. Grounding to the engine probably works easiest where the stomp starter linkage bolts to the bell housing, but you can use any bolt. You should also have a ground wire between the frame and engine. Here's where that frame to engine ground is on AD series trucks. The stomp starter linkage was already removed when I took that picture.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
