When I pull out my headlight switch with the instrument dimmer turned to 'off' everything works fine. When i turn up the instrument panel dimmer... instruments light up but my voltage meter progressively goes backwards ending up pegged at under 8volts and the battery gets drained as I drive at night. Is this indicating a failed headlight switch? Or do I have some wires crossed somewhere?

fail or no fail? Looking for someone who knows symptoms of failing headlight dimmer switch.

Try cleaning the contacts on fuse #9 they might be dirty.