We ahve all gone way off path from your question. It has been answered. No need to discuss measuring. The R terminal and resistance wire is wired at least two ways depending on year and probably whether Chevy or GMC. But we/you are using these methods on trucks that were 6V, so a person can choose several bypass methods when converting. The methods and the wiring changed several times and folks mix and match and tricky ideas. In a discussion like this the methods can get mixed up. None of it is difficult.
My quick list
1. Ballast with foot switch side terminal
2. Ballast with electical relay/solenoid (A and B)
3. Resistive wire method A. (R terminal)
4. Resistive wire method B. (R terminal)
5. Separate SS581 relay trick
6. Various ignition switches, including push button, Ign 2
HEI, pertronix and all that jazz
Last edited by bartamos; 02/07/2023 11:15 PM.
