Using a heat conductive glue I fixed a 2mm thick aluminum “L” piece (partly visible on first photo) to the box and then glued the bare led to that “L” piece. Spot led is on 20mm star glued directly to the backside of box. The light gets warm with flood on high and warmer with spot on high but not hot.
I needed thick lexan so it can put enough pressure on seal. I have some experience with my custom duo (bare led) and Zebralight H600F (floody lens) and I prefer bare led for flood especially if light has separate spot. It gives you better perception of surrounding.
I wanted to protect the switch from breaking and accidentally activating. A must for a caving lamp. For first try I just put two 18650 holders in parallel. I plan to make a waterproof battery canister. If successful I’ll post about it.
Thank you all for your comments. I’m glad you like it.