Need help with a Dodge Charger question.

Hello All: Cruiser here. And yes, I know this is a B-body question, but here goes anyhow. I was driving my very stock 1969 Charger last night. About 35 minutes into a 60 minute drive, I noticed the ammeter was flickering pretty wildly between plus or minus 10 amps. I also noticed that the headlamp switch was noticeably warm to the touch. I had the high beams on at the time. When I switched the headlights off, the ammeter returned to normal. I didn't notice if the headlights were flickering with the movement of the ammeter needle, as it was still light out. The car has a solid state voltage limiter in the dash, the Mopar electronic ignition conversion, and a solid state voltage regulator. I didn't notice any unusual melting or heating at the bulkhead disconnect. So what's going on here. I was quite concerned about the temperature of the headlamp switch and I don't want to start a fire in my dash. Could it be a problem with my foot dimmer switch? Headlamp switch? All underdash wiring is very stock. Ideas?
I'd start with replacing the floor dimmer switch if it's been in the car awhile. They're cheap and prone to all sorts of corrosion and headlight problems. After you change it, see if the headlight switch still heats up.