If the car in question is a 1964, you should have searched for my post
www.forabodiesonly.com/mopar/threads/fuel-gage-fix-64-valiant.269976/
Your fuel gage terminals look different than mine.
I tweaked the Vreg output so that the temperature gage read correctly (test resistors) and added resistance in parallel to trim the fuel gage to read correctly w/ the new fuel gage. The gages also have mechanical adjustments (a bit tricky).
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