Good used PCB that has no burns, corrosion or separating areas. The red PCB (printed circuit board) was used in the latter part of 1969 (from 2/17/69 on) and all of 1970. In 1969 if you had a white plug connected to the PCB it used a red PCB, if you had a black plug the blue PCB was used.
This is an example of the 1970 XR7 underdash wiring harness plug.
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