Three connectors and heavy wiring. Likely a heavy duty system. Lets figure it out.
Begining at the battery. Red wire (A1) goes to the starter relay shown here.
View attachment 1716023035
We see a junction here with two other wires. One large red wire and the other a black? fusible link.
Next.
View attachment 1716023029
View attachment 1716023032
Not what we are seeing here a the grommet - Other than its probably to the ammeter. Will come back to this.
We also see a red wire to a connector possibly going to the multicoasdfnnector.
View attachment 1716023033
Looking at this one we see another red wire and connector that may be going into the multiconnector.
Do you have a picture of the original voltage regulator and connections?
Let me get my dinner cooking and will come back in bit.
This is an ammeter cable from another dash I got for replacements. I could just replace the cables, check the alternator as 67Dart273 said before and see if this makes the job...?
This is the original VR