My spacer is a bit more complex, the Ultrafire lens is a lot taller than the Carclo and 21mm diameter. No mounting feet so I’m trying to make pockets to support the sides of the lens. It’s tight but it fits if I draw it out on paper. I’m having a hard time with setting it up in the four jaw chuck in the lathe accurately enough.
That light of yours is just a monster. 200 watts is about what it takes to run a 1/4hp motor, the motor is much more efficient and still uses a cooling fan.