Hey All, I have a used but in superb condition original M3 combat light. I bought a surefire tape switch for an amazing price direct from S/F and want to turn this into my every day weapon light. Years ago I had the actual weaponlight made by surefire and really liked it. 'Clearly by today's standards it is grossly underpowered.

I was thinking of upgrading the head to the newer S/F M3LT that I just bought at a steal. Will this work?  Seems like the new head would work well on the body of the older M3 light.

What would be a good mounting solution if this in fact works out for me?

I built a 12v light and used a turbo head and it was a great light.  I have moved away from cr123 batteries and am using rechargeables.  

If you haven't already bought one and want a high intensity light for outdoor use look at the Olight rechargeables.  They are lighter, brighter, and have multiple brightness settings.  

Mounting.  I use a few.  I have an Elzeta, I think a magpul(best for a longer distance light),  and use basic scope rings.  

Look at the spot and throw of the lights.  Match the light to the purpose.  Do you want to light up every corner of the room or ID a coyote at 200 yards?

Sorry for not reading the entire question.  

The M3 is a great light.  Call Kevin at Brightflashlights.com.  He can fix you up with mounts, cr123 batts, a drop in LED max lumen output, and/or rechargeable options.