Hi HorizonSeeker,
I hope Alterman doesn't mind me popping in here. I purchased his conversion kit for my 8X, paid $55 for it. The sleeve is well machined, and works perfectly first time out. The tailcap button in its stock form moves the entire battery pack fore and aft, making it feel weird if you are used to modern torches. The included McClicky makes this feel much more responsive.
In short, you will not be disappointed!
~D