Melting my brain headlight/ignition/dimmer issue. 04 Silverado

[Barry1965]

04 Silverado 4.3 excellent condition truck 125k miles.

I parked this truck inside my shop in March with good intentions of replacing the clutch. I finally did it a couple weeks ago (very busy ). Clutch/transmission easy. No problem.

Here's the issue...

Headlights on dim, BOTH bulbs on passenger side on very bright. BOTH bulbs on drivers side on very weak. All at the same time,not normal. Flip the dimmer on the turn signal...the engine stalls. The engine will not shut off when I turn off the ignition. I shut it off with the dimmer. Never had an issue before. I've checked grounds. I've checked relays. I've checked to see if hungry critters have been chewing. Nothing. I'm thinking it's POSSIBLY the multi function turn signal switch? It may POSSIBLY be the ignition switch?

Before I start ripping this great truck apart, has anyone experienced this? Any ideas? My hair is already gray, I'm ready to start pulling it out.

Any and all help is greatly appreciated.