the 17mm one fits just fine. did it just the other night /ubbthreads/images/graemlins/smile.gif
The thing is,,,
The LS is kinda holding it in place.
The new style reflectors hace 3 little legs. and dont have the outer sleeve,
so, they are shaped more like optics, and you might be able to use the optic retainer ring to hold it in better,
then when you tighten in the LS/circiut/heatsink just snug it up on there nice, if you tighten too much, it will smash the LED.