[mickmate]

The headlights use either plastic (modern) or metal (original) buckets. The plastic ones are OK in that they don't rust but as you know there are some plastics by name, not so much on the properties. They should have a boss or tab on the bottom, slightly off center, that takes a retaining screw that Ned mentions. Look for the boss or tab for the screw on yours. These have a groove around the top to hold the edge of the ring, they swing down over the bottom and align the screw hole with the boss. Some of the TR headlight buckets I have seen use a trim ring that snaps on. You need 5 hands, your tongue out your left side of your mouth etc to get them hooked over on the edge and wriggled and encouraged progressively down the sides. These have either a groove or clips pretty much all the way around. They are a trick for sure. If you don't have the screw hole on the bottom you might be able to change out your rings to that style. Also note at the same time you're playing with it and they are either 2 adjuster or 3. There is also a rubber gasket between the bucket and body, and a dust seal behind the ring many people leave out. I find that is a nice protection against excessive moisture rusting up your adjusters. If you don't have facility for a retaining screw you can change out the buckets noting of course some of the previous features. The irony of all this rambling is I'm about to hit the words "post QUICK reply".