Yes. They are 0.6" diameter
I don't know which mount you show a photo of.
SureFire's M78 Mount is intended for the E-Series.
Sorry bout that.
I want to mount a Surefire E2E Executive Elite with the mount shown, which is Vltor mount designed for "E" series lights. But mine has a clip. How do I remove the clip? LOL sorry the dumb question, might as well ask it.
1) unscrew bezel
2) remove SF123A's (in case they go flying)
3) carefully remove the o-ring (kinda roll it over and off the threads).
4) using paracord / bootlace etc, threaded in the "U" of the clip - pull/wiggle* the clip off the bezel-end (notice the threads are flat to allow this) while holding the battery tube.
*Notice there is a black plastic widget under the clip (to prevent the o-ring from squishing under it when the bezel is on tight) - this will go flying unless you are careful so watch out for it!
With the clip removed the widget can no longer be used so the o-ring will be able to afford the same level of weather resistance. You may find the weapon-mount you are using allows for SureFire's short pocketclip to be used. I'd say there was about an inch of body spare with the short clip installed.
I hope this helps?