ok so I think i'm just gonna get a p7 flashlight off dx instead of doing a full custom, then what i wanna do is drill a hole in it and wire it for an external batt, the batt i wanna use is from my old niterider, its a 6v so i need to drop that to like 3.7 somehow, i figure i just throw a resistor in series and i'm set, problem is idk what ohm resistor to use any thoughts?

second thing is the mount, https://www.dealextreme.com/details.dx/sku.13004 this one looks good but i have 31.8mm bars, will it fit? otherwise what adjustable angle mount will fit oversized bars

thx