Solved with a Meter Match Fuel Tank Sending Unit/Fuel Float Adjustmet

If anyone identifies a source for the nichrome to rewind our own boards, that would be great.

For repair places, add John Wolf & Co to the list.

The other problem with the replacements is the float arm length.
See Fuel Sending Units and A-Body Fuel Tank Map
also seen in the following thread where
@Cuda Al shows his repair in detail -
Fuel Sender Rebuild

as does this How to article (except he gave up on fixing a board with busted wire )
OEM Fuel Sender Repair 1967 Dart

As far as which arm and pickup tube goes with what year
"In the mid sixties to the early seventies the part number was 2421493.
From around 1973 to 1975 or early 1976 the number was changed to 3621515.
Then Chrysler changed the number to 4051004. When they went to the newest number, the float was plastic. I recall seeing a Chrysler memo telling why they changed to plastic floats. They said because of brass corrosion caused by small amounts of moisture in the fuel they changed floats to plastic."

Part numbers I looked up in the FSMs were:
1967 p/n 2257 493
1973 p/n 3621 615

Several changes in fuel formulation in th 70s. One of them may have resulted in greater reaction with brass.
We chatted earlier about this subject. If you can start a thread with links to threads, websites, and repair sites I can make it a sticky. PM me to discuss.