This mod is provided by Mark L.:

The Ray-O-Vac 2AA swivel-head plastic flashlight is a practical flashlight for a Luxeon Star w/O mod. It is a pocketable, flexible form that's very practical, if not very glamorous. The light clips to a ball cap, or to other spots like a shirt or jacket so you can work hands free. It stands on its bottom and makes a decent task light. It won't roll off on a surface if laid on its side. The donor flashlight is relatively inexpensive (less than $10 ... I don't remember the exact amount) and is available in hardware & discount stores. The only drawback to this light other than general aesthetics is that it isn't waterproof.
Although not a difficult mod, it requires a fair amount of filing or access to a Dremel tool, and intermediate soldering skills.

The National Semiconductor LM2621 DC/DC step-up converter evaluation board is adjusted to provide 3.1 volts to pump up the 2AA batts enough to drive the LS at around 310 mA. Details on this circuit modification are available at http://thelightsite.cruxial.com/mods/mods_index.htm. Although it would be nice to drive it the LS harder so it is even brighter, heat becomes a worry and since in this mod the LS is encased in plastic without a large heat-sink, the 310 mA level is just about right. Neither the LS nor the DC/DC stepup converter get warm. The 2621 PCB has to be cut down just about as small as you can take it without removing any circuit traces. Some of the other DC/DC PCB's noted easily searched on Candle Power Forums might be better choices for this mod, but the National evaluation board requires the least effort.

The LS heat sink must be trimmed on two sides flush with the black plastic collimator retaining collar, and the corners have to be rounded as well.

Mounting the LM2621 to the bottom of the LS aluminum heat sink keeps the light module depth shallow enough to fit in the head, and allows enough room for a thin (1/16th inch) layer of rubber to be sandwiched between them to help isolate any heat the LS generates from the LM2621. "GOO" All Purpose Adhesive™" worked great to make it all stick together and then, after wiring the LM2621 to the LS and attaching leads for power, some 30 minute epoxy nicely pots the converter to protect it from any moisture or rough handling.

Inside the flashlight's spherical head, the housing that held the lamp assembly must be cut down so the LS and converter will fit. Also, inside the head there are two plastic hinges that allow the flashlight head to tilt. Both hinge posts protrude into the cavity and must be shortened so the new LS assembly will fit between them. The shortening isn't difficult, but needs some care so you don't shorten them too much.

The reflector comes apart from the screw-on collar after a small struggle. Gently rocking the reflector back and forth while holding the black plastic collar ... pulling and twisting ... will get them apart. Cut out the reflector's base just enough to get the LS barrel through. The reflector plays nicely centers the LS in the head when it all goes back together.

Once I determined which were the positive and negative leads in the bottom of the flashlight, I soldered the converter's power leads to them. Then, with some nudging and minor fitting, the flashlight easily reassembled.

This one, my last finished modification, is a more than little on the gaudy side, but it is very easy to locate at night when I'm camping. I put white and red 3M Scotchlite films on the sides so it flashes when hit with light from another flashlight. I used some Nichia blue-green glow powder paint below the switch and Alien Skin on the opposite side so the light shines in the middle of the night when nature calls. The reflector is also covered with glow paint (which is slightly charged when the light is on), so no matter the flashlight's orientation, some glow always shows.

This is a handy, pocketable, flexible flashlight that provides about 2 hours of very bright light, a couple more hours of moderate light, and many, many hours of 'moon-mode' light.

A tip of the hat to CPF member 'Silviron' who first modded the Ray-O-Vac swivel head flashlight with a single 5mm Nichia white LED in July, 2001; and to CPF member Quickbeam for his detailed instructions on converting the National Semiconductor LM2621 evaluation board.