Suggestions for a couple of mods

Hey guys,

I’ve been lurking here for awhile and finally decided to join as I need some advice. I have a few flashlights that I intend to modify at some point as they are rather poor performers. As of yet, I have exactly no experience modding flashlights but have been learning some from this site, but please be as specific as possible with suggestions, and links are always helpful! The first two lights I intend to mod are a non-led Surefire P6 that is something like 6 years old, and a Trustfire F20 that I recently received with an order.

For the Surefire, I intend to bore the body to accept 18650 cells, I would like to add a pocket clip, clicky switch, and am looking for as much throw as possible from this light, low medium and high modes would be nice as well.

The F20 I received was advertised as having 5 modes, when I received it however, I found that it only functions in one mode, and, prior to disassembling, cleaning, and reassembling with a copper impregnated conductive grease on the threads, was very prone to flickering and even shutting off completely. For this light I am also looking for more throw than flood, having at least a medium and high mode would be nice, and I would like to be able to use AA and 14500 cells.

Thanks in advance for your suggestions.