Converted 49 GMC to 12 v negative ground system with alternator. Put voltage reducers in front of both gas and temp gauges. Gas gauge fine. Temp gauge not reading. Engine is 230 CI out of a 62 Chevy. Replaced engine temp sending unit with new one that has a 'G' terminal which I think is for gauges and 'R' terminal for a light used on later models(same as was on engine originally). Have tried swapping [/LIST] both terminals to the single wire to the low temp side of the temp gauge with no reading on gauge. Gauge shows continuity when checked with ohm meter. Also will peg to high temp side if I shift polarity on back of gauge. Pretty sure gauge is good, but do have another old gauge that I can try. Have refaced my gauges so hoping to keep from replacing or buying new 12 volt temp gauge. Everything else is working fine and have had no other wiring issues. Hoping to get dash and wiring done so can move on to rest of truck. Putting together from pile of parts so new challenge every time I work on it.
