Finally got around to troubleshooting the light problem and I need to pick some brains that know more than I about 81 era P30 systems.
Problem; nothing works that uses the switch. [Head and tail and clearance and dash lights]
Turn signal and brake lights work.
Pulled switch out, tested with light, no apparent power going in to switch. Found a way to hot wire power in to heavy red wire going into switch. All works. Can't find where red wire goes and gets it's power when it's working.
If nothing else, I thought about running a new wire from the battery or some other source to the switch. Should I put a fusible link in this wire? 20 amp? Any thoughts appreciated.

Your red wire goes into a bundle of other red wire behind the dash. A 10-12 ga yellow wire (on mine) goes to the DC electrical panel where it is connected to either a copper bus or to a terminal strip that is fed constant 12v regardless of the ignition switch. Now is a good time to convert the full power draining switch for your headlights to a relay activated one. There are a number of threads here that walk you through the job. That improves the headlights and stops your dash panel from having to switch 20 amp circuits. Headlights are not normally fused or linked to a fusible link.

Danny, Don't know if this will help. A wire diagram for a 81 Olds shows a red fusable link wire that comes from the starter lug. Same lug that the battery cable connects to. From there it splits and goes to the fuse block. One goes to headlights other to tail an dash.

Danny, the closest thing I have is my 86 wiring diagram. (It is also here on the site)

The headlight circuit is designated circuit 2 and is wired red directly from the back side of the fuse block to the switch. (unfused since the headlight switch has an internal circuit breaker)

On my fuse block, the turn signal flasher is lower right. On the left side there is a 20A fuse for the tail lights.. directly behind this (on the back side) is where the red wire should be attached. Check to see if you have power there. You can always run a nice fat wire from any good 12V source right to the switch, put in a relay etc.

Thanks all. I'm starting to get a handle on this now. If I'm seeing it right, the power goes direct to the switch, then out to the fuse panel, where fuses are for the tail lights, insrument lights, etc. The hot spot I used for testing was a solinoid terminal top front passenger side of engine directly over the alternator. This would be a simple place to wire to permanently if there are no issues I'm missing. I still have to find the notes on relays and see how to do that, as everyone says it helps. Might as well do it the best way I can.

You're on the right track. If you run power from that point to the switch, you'll be back in bidness.

To jazz it up, you just run another big wire to a breaker then to the 2 relays. Wire each relay directly to the headlights, one for dims, one for brights. Use the old headlight wires (and switch) just to fire the relays.

You know... I'll be heading for the Keys in a few weeks... Planning to visit Lenny and Judy Feb 27 and 28, then March 1 to the Keys. If you're not in a huge hurry we could stop by...