Lunar, If you remove the screw the heatsink will be loose and only hanging on by the LED wires, then you have to desolder the LED wires from it and it will come out. That screw holds both the heatsink and the converter in place. You then have to remove the bezel ring, window, o-ring, and reflector to get to the led and heatsink, they come out from the front. I can't say that I notice a big difference in output with the UWOJ, I'm sure it there but not really noticeable to my eyes. I really like the tint of the WO much better than the stock YO. The Cu heatsink does transfer the heat better than Al although I don't really think is was needed. I didn't have a spare one so I figured I would just make one. I had both Cu and Al in stock and I knew Cu had better thermal properties, so I made it out of Cu. I did get in touch with Don and bought a spare one from him. Those where a little harder to make (for me anyway) than I thought they would be. Don did tell me his is going to have a universal heatsink available soon that will allow mounting of different LEDs, like the K2 and some other makes. I did I runtime test before and after with the same battery (MP brand R123 700mAh), I got 1:08 with the TYOH and 1:01 with the UWOJ, so I only lost 7min with the higher Vf of the J. I can't really comment much on putting a Lux V in a Ti host, heat maybe a problem. I know these get rather warm with just a Lux III with a lower Vf and only being driver at 525ma or so. I would be nice to see a luxV, but I know I'm not going to be the ginny pig on that one.:lolsign: