The left headlight on my 73 has an uneven gap along its front (curved) edge when its in the down position. The gap is very narrow (2mm) on the inboard side and very wide 8mm on the outboard side. Is there a way to rotate the headlight assembly to the right (clockwise when looking down) to even out these gaps?

Check inside the fender, and inside the trunk. You'll find that the pivot for the light is bolted on in those locations. You may have to clean off a lot of undercoating/dirt for the outboard one. You can loosen the bolts and move the pivots some. This will move the whole headlight, so it will alter the gap at the back of the light as well as the front. And the sides.

If the uneven gap is because the front of the car has been hit and is no longer quite straight, it may be best to leave it as-is.

--DD