New Instrument Voltage Regulator (IVR) Idea

I used one on my 1964 Valiant, 1965 Dart, and 1965 Newport. First one was sold on ebay as "Plymouth Voltage Limiter" for ~$30. The others were from Amazon as general DC supplies for maybe $10. They looked identical to the ebay one. One might have been non-adjustable and only $8. Adjustable is better since you can tweak the voltage to get either your fuel gage or temp sensor to read perfectly (not both) at full-scale (or zero). I had to add ~20 ohm in parallel w/ the dash fuel gage to get it to read correctly with my new level sender (in bench test), after tweaking output to ~6 VDC. The gages also have screwdriver mechanical adjustments for zero and span, but intended only for experts in the factory, though I figured them out. Be careful since they bend metal parts.