I've modded a Scorpion LED (same type of module...slightly different dimensions, but overall same design as the TL-2 LED) to SSC P4. A Cree is harder as you have to modify the reflector. The SSC P4 has the same radiation pattern as a Lux so works perfectly with a Lux-based reflector if raised approx 30mil. See the link Scorpion LED SSC P4 in my sig below for pics.
Oh, you have the Gen1 version that's not regulated. Can't tell from your picture, but if the leads of the LED are accessible, you can swap it. Still would be easier with a SSC P4 than a Cree XR-E.