I took some old switches and robbed a contact out of them. I got an old double clad board and cut out some rectangles and soldered the contact tab to one end and bent it around to the other side. Soldered a couple wires on one end and presto, pressure switches. I wraped them in self adhesive velcro and you wouldnt believe how good they work. Put a little matching velcro on the riser.

I bought some of those little Mag Lite adapters from Bass Pro and modified those. I drilled out a counter sink 1/2" dia the depth of the PC board where the spring goes and made some disks out ot the double sided board that were a press fit. then soldered the spring to one side and soldered a wire to each side of the disk. Press the disk into the adapter after feeding the wires through and one side makes contact with the base and continuity is broken by the disk. Everything stays in place for changing batteries. A little shrink wrap here and there for strain relief and they turned out great. I just shot a 3" group at 35 yds in the dark.