[Above is from a thread in the truck forum by Royhldn called "Bully".]
Question: Is there a 6 volt temp gauge that can be converted for use in a P15? If I recall correctly, '55 was the first year for 12 volt systems.
[I have a '55 engine in my 46, and rebuilt it with the late model head before I realized that it does not accept the mechanical sending temperature unit. I do have the head from a '49 1st series, so I could swap them out, but I did a lot of work on this later model head - vatted it, bead blasted, and cad plated - so hate to loose that work. If I can't go the electric route, then I will probably have the head drilled & taped for the larger diameter fitting used in the P15 head. I didn't want to convert to 12 volts, but I know that would be another option.]