im surprised the heat from the sun was enough to properly loosen the glue..
It's a longer story. What happened is I drove about 30 miles to drop a painting off to be framed, and then, while waiting in the parking lot,
I impulsively decided to rip apart the headlights (since I had nothing else to do).
The black goopy sticky glue was strong, but the real problem was I didn't remove the T10 Torx screws until I was home. Only then did the headlight come apart for inspection.
Here is the impromptu 10-step parking-lot headlight disassembly DIY!
After removing the four 8mm bolts holding the headlight and pulling the headlight out the front, pulled of this weathered rubber molding and another blue-painted strip.
I then pulled out the high beam H7, the low beam H7, the angel eye (AE) bulb, and the orange side-marker bulb. Notice the yellow covering on this side marker bulb flaking off for some unknown reason.
With the screwdriver from the trunk emergency toolkit, I started prying the cover off. I started at the unused-european left/right switch flat spot at the top and undid the clasps as I pried ever so slightly outward.
Here you can see the sticky black glue starting to separate, ever so slightly, with leverage from the screwdriver. Constantly, in the beginning, I had to unclip the clasps on both sides until their locks were clear.
Working around the headlight, two or three times, I was able to slowly, over the period of about 20 minutes or so, get it to pull further and further apart, right there in the parking lot.
I didn't realize it at the time, but it held up strongly at the side-marker end, due to the two T10 Torx bolts unbeknown to me at that time.
These two T10 Torx bolts should have been removed (but I didn't have a Torx set in my emergency toolbox).
While I shook the headlight, something rattled, and out fell the cellis ring, a reflector ring, and something fell to the engine drain pan as I could hear it stop on the plastic.
Grabbing the other emergency screwdriver end (the big Phillips), I unscrewed the 9 single-turn screws on the lower engine cover and found a part of the headlight adjuster had fallen down.
While lying on the ground, in the hot California sun, I pondered my surroundings, which I found surreal from that perspective, as if the BMW was out to eat me.
Luckily, it was almost as if there was a tall thin alien being standing over me, protecting me from the maws of the BMW, looking quizzically with one huge alien eye, at what I was doing to my bimmer!
I stowed the headlight in the trunk, picked up my now-framed painting, and headed home to ponder what was wrong with my headlights.