I have had my S15 apart (several times) for an LED swap (XPL). I would suggest doing the adjusting from the inside. Snipping/trimming the rubber stem MAY be the answer. I would do it after testing other failed reversible methods. Unfortunately for me, when j removed my LE for the first time, a tiny amount of rubber was snipped off. It sets in a recessed area in the pill making contact with the clicky. The recess has sharp edges that apparently sliced off some of the stem when removing the pill.
I don't quite have it where I want it yet, but I put a dab of JB Weld on the metal clicky button & stuffed some dense foam into the pocket. The initial slice of stem was too much and didn't make contact when reassembled. Although it appeared that it was just a very small piece taken off. I may have taken more off myself, had I been trying to adjust the height myself. Anyway, it's usable now and definitely have to make a conscience effort to turn it on. It fixed that problem, I'm just not happy with the "feel" of it. I'll work some more at it, at some point.
If there is a way to remove the button from the body, before/without disassembling the light, it would be the way to go, IMO. If anyone knows how to do that, please let me know.
...I carefully pushed a little from the inside out, trying to push it out to no avail. I'm assuming it's glued in, but not sure.
The problem I see with trying to shave down the height of the button from the outside, it may not be a solid button. The underside of the button may be hollow. Without completely disassembling the button, it will be hard to tell if it's solid or just a shell. There's definitely a rubber stem protruding out of it. So, it might be hollow to help hold/align the rubber stem. Trying to shave it down without knowing for sure how far you can go, is too risky for me.
It may have been a fluke that my stem was damaged while removing the LE. I'm sure that it is a possibility though. So be careful if you go that route.
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