Thank you, Curt, for the well-considered responses.
In all the years that I've been using a weapon-mounted light, it's been activated for no longer than many seconds at a time. I don't think heat build up would be a problem, at least for me and how I use them. A brighter LED with the necessary driver installed in that conversion unit could be just the ticket. Would a TIR optic work in such a small space?
You raise the very valid point about accidental shootings. When I train people, I stress that weapon-mounted lights are not for beginners or to be used for searching or utility lighting. On duty, I always carried at least one hand-held light in addition to the one on my sidearm and practiced quite a bit using both simultaneously. The weapon light was only activated if pointing the gun was warranted. Even then, it was done in a flash-and-move fashion.
With the rifle or shotgun it's a bit different due to requiring two hands on the weapon. I prefer to bounce the light off of the floor or known safe direction, again in a flash-and-move fashion.
Sorry for the thread derail.
Once the unit arrives I can take pics and measurements for posting if any modders are interested.
Thanks,
Lee