No prob. I tried reversed early on, but I probably already had tightened it up, so didn't try hard enough.
Edit: took all of 2 secs to loosen the end cap now - CW, reverse, etc. .
So I see the driver and the issues - tight space, plastic ring it fits in, switch on the back side.
Looked carefully at it - probable a PIC, SOIC-8, Vcc on pin #1, switch on pin #2, FETs on pin #4, and GRND on pin #8. And that seems to be it. The FETs are two in parallel, 3 pins, output goes thru a bank of parallel current limiting resistors.
So, 4 wires, that's all. I'm thinking of removing the MCU, using an 85 in it's place and hand wiring up the 4 pins needed. Should be enough spare room on the driver. Dunno how well it will work. I'll probably replace the 'D1' diode they have with a 4.7 ohm resistor which the 85 typically needs.
These are the tools I used/tried:
It lives in pieces!
The driver:
The (my fault) damage:
I'll sand down the end cap to bare - should mostly hide the scratches, not too concerned about them - this light will get used.
NarsilM has one channel support, so should work - might jumper the resistor bank though for more power, or leave as is since normally I don't need power so the lower the max amps, the more efficient it should be.
This pic datasheet on page 4 shows the pins where Vcc and Vss are: https://www.mouser.com/datasheet/2/268/PIC16(L)F1831318323