In my limited way of looking at the world, it seems like you have two options with mounting a clip on an LS. Actually, maybe 3.
1) Drill holes into the body and attach a clip like you find on a knife. Requires precise work and skillful tapping.
2) Mount something that is a clip that is on a ring between the TSP and body. I think this would only work with a Clicky, though, because the twisty would give it too much play. If it's like a First Run with the separate body and end piece that twist off you could put it there, though (lens up pocket carry). Has anyone done this before?