this is about the easiest 3aaa-18650 mod.
simply lock it out,drop in a spacer sleeve,and drop in an 18650 flat top.
instantly reversible.
you lose the lockout on 18650 but its not terribly prone to accidental activation.
about 800ma on hi and just barely gets warm.
i used a 3d printed sleeve meant for 3aaa cheapies and it is snug.i can still get it out without too much trouble though.
upgraded led to a Sedstar special 4500k xp-g.
much nicer now.
bezel glue is tough though.
tested the warranty on the strap wrenches i broke getting it open.
they were replaced but with a note that they were not gorilla proof.
i guess not flashlight proof either.