Why 10.7 volt input at ‘71 Duster instrument panel?

All - I just reviewed inputs above and I’ll need to re-read a few times to totally understand all of the suggestions. Cutting to the chase - I got the voltage up some and reinstalled the instrument panel to check everything and take a short test drive. The fuel and temp gauges now work, blinkers are stronger, dash lights now working, and car starts and runs great.

I’m sure that I was on the right pin.

Ground is good and I’ve done a lot of connector cleaning. Did not go inside steering column to inspect/clean starter switch.

I used multiple meters and they agree on voltage data.

I do have points and, when I checked, the ammeter was substantially deflected with switch in run position. After disconnecting coil and alternator - much less ammeter deflection (still some) and voltage was up to 11.2 V. With charger on battery - voltage up to 12.3 V with run switch on.

The sad news is that my speedometer - tested for the first time yesterday after repair - is making a bad clicking noise and I’m going to have to pull everything back out and probably ship the instrument cluster back to shop that did the repair. At least it seems to correctly register speed but sounds like it will self-destruct if I continue to use it. (The speedometer shop told me - before sending the speedometer back - to inspect the new speedometer cable to make sure the center flex cable is in the correct position).

With the instrument panel out - I’ll have the (unwanted) opportunity to further pursue causes/fixes for the voltage drop at the cluster input pin. I can’t wait to go out in the Florida heat and pull the instrument panel out.

Thanks again for your help.