Looking at modding a mag or two and looking into the heatsink.
I found some spot welder tips here at work for a welder we no longer have
I’m thinking of trying to reflow a xm-l onto one of these then I can scew it into my heatsink. It make a nice post so I can get it into the reflector easily and the what not.
Thinking hunk of aluminum for the the main heat sink and then one of these for the pedastal
Speedy Metals for the aluminum. You can order cut to size. It's best to buy a dozen or two (see if others want to go in on it), so the shipping per is better. I use 1-5/16", 6061 round stock and a piece of 28ga (0.012") thick copper wrap. It makes a heatsink that fits tight into a maglite.
I bought about 15 of the cut to length (1/2" and 3/4"), heatsinks and it was about $2.50 each. Add a buck or so for the copper and it's an inexpensive alternative to a custom heatsink.