Took about an hour...not super hard.
This video was the most helpful.
Sadly the used replacement part isn't factory GM......it's Chinesium.
Once installed, I found that up is down and down is up.


All the door clips held up and I didn't lose any bolts in the door.
I think the hardest part is getting the angled grommet to fit right.
Also, don't forget to roll down the window first (so you can get to one of the lower bolts).
The gasket was shot, but I set it as best I could and reused it. Hindsight: some thin double-sided tape might have worked too.

It went to the shop today to get the solenoid actuator and purge valve replaced.
Monday it's getting a new power steering pump and hoses.

My youngest is moving to Butte, MT........so there's gonna be a new shiny black H3 in town.

Come spring, I'll be looking for the ultimate Hummer unicorn, a H3T Alpha in Boulder Gray Metallic with Light Cashmere interior.
Fingers crossed.