Ok, I've attached a couple of pictures. First off, this is the order (from the body out to the lightbulb itself.)
Gasket goes behind main bowl, It only fits one way
Smaller bowl attaches to main bowl with a spring.
https://tinyurl.com/4plmkw The spring hooks into one of the holes in the centre ring (I think the odd one) and to the flange attached to the inside of the main bowl.
The lightbulb goes into the small bowl and is held in place by the chrome ring that lays over it.
The trim ring fits over the whole thing once installed.
There should also be three bolts to hold the unit to the car, one of which has a clip for the wire harness to be supported.
About the only trick is the adjusting screws. They are the longest screws and fit in the two slots (not holes) in the small bowl. They then screw into the big bowl and extend into the two "tails" that should still be on the gasket.
The head of the screw has a flange around it about 1/8 of an inch down - this area slides into the slot on the small bowl allowing the small bowl (and therefore the light) to move when adjusted.
You can see the adjusting screws at 10 O'clock and 2 O'clock in the picture below and the slots at one O'clock and 4 O'clock in the pisture above. And no I didn't align the parts before I took the pictures. Hope this helps - I'll check back if it doesn't
JP
https://tinyurl.com/66x8jl