charging issues

Since you have the cluster out, you should take a REAL hard look at it. Here is some of the stuff that was wrong with my 67:

Many of the harness to cluster pins were broke, loose, corroded, a common problem. So many of mine were broken, I opted down to Radio Shack and bought a pair of "Molex" type connectors, and soldered short jumper wires about a foot long to the PC board in place of the pins, and connected the Molex connectors there

Inspect those pins, clean 'em, and if any are loose solder them to the board.

The temp/ fuel gauges are held to the board electrically and mechanically by nuts. Replace those nuts, and put star washers under 'em

The socket for the gauges voltage limiter has brass fingers in the board. On mine, these were not making good contact with the board traces. I soldered mine to the board. A better way would be to solder very short wires to the brass fingers, and then in turn solder the jumpers to the board.

Loosen/ tighten the screws mounting the board to the cluster casting. This is the ground path. Also, pick one good accessable screw, and put about a 1 foot wire under it with a ring, and drill a hole in the column support behind the dash, bolt the other end of the wire to the column support with star washers

Inspect and clean the pc board around all the lamp sockets. Sometimes the copper gets dull and corroded, sometimes it becomes eroded.

Inspect and replace bad lamp sockets. Sometimes, just bending the contact fingers on the sockets out some helps

Make sure your limiter is OK, or replace it, preferably with an electronic one.

'S all I can think of fer now