Main dipped headlights not working

You need to go back and re-read what was said earlier

Have you obtained a service manual and wiring diagram yet?

You may have multiple problems. To repeat what I said earlier:

THE HEADLIGHTS ARE POWERED from an UNFUSED welded splice in the black ammeter wire. This splice/ branch leads DIRECTLY to the headlight switch ONLY for the headlights.

Go DIRECTLY to the foot dimmer switch. See if you have power there ON TWO TERMINALS of the dimmer. Switch the dimmer. One terminal should go dead, the other should be hot. At all times with the light switch in "head" the dimmer should have TWO terminals hot.

From there lamp power goes out through the bulkhead connector another likely spot.

I dislike having to repeat