LED Upgrades for Streamlight Weapons Lights?

Hi all. I have about 6 Streamlight weapons lights because at some point or another I got a great deal on all of them. Mostly consisting of M3 models but I also have an M3X, M6X, and TLR LED. My question is... custom or drop in, is there a way to convert these to efficient LED. I have a Malky drop in for my Surefire G2L and it puts out 80 lumens for like 6 hours and then deminishing light for up to another 6 hours. I don't understand why my TLR (Which puts out 80 lumens) doesn't run as long other than it's just a less efficient emitter. SO... I would love to turn that TLR into something like my surefire and would love to upgrade my other incandescent weapons lights over to LED. And to be honest, something in the neighborhood of 150 lumens for 2 hours would be perfect. Even in the plastic bodied lights I think that wouldn't be much of a heat burden since weapons lights are only run for seconds or minutes at a time. Only in the rare extreme situation does anyone run a weapon light for 2 hours straight. Doing so kinda draws fire LOL. I did a search for this and didn't find anything so I thought I'd ask. Sorry if this a FAQ.

With regards to the TLR-2, you can do an emitter swap to up the output.

I put a Seoul P4 in mine and it there was a nice difference.

The emitter swap is usually pretty straight forward.