Panasonic 14,4v 3Ah Li ion tourch for Battery drill, Led conversion

I have a flashlight running on the batterys from my battery drill. It's this one
http://cgi.ebay.co.uk/Panasonic-EY3740B-14-4V-Cordless-Li-Ion-Flashlight-/270520134854?pt=UK_Home_Garden_PowerTools_SM

14,4V 3Ah Li Ion. I wan't to get some led's in it instead of the bulb present.
By dooing this i want more light. Only number i seen is 4000 lux (370 lumen ???)

It got a cirkular room of 75mm wide and can stretch to 50mm deep. Have to fit reflector and led's. Beyond that is a square room of 40x30mm 30-35mm deep.
Any suggesting what to put in it? A driver could allso fit in the handle. Or is it best to direct drive it with a voltage restrictor or what it's called? (prevent to high voltage, ex if led is max 14v and battery is 16v

Anyone? The bulb present is 14,4v 0,55A It's over 16V fresh. Anything led'y to put in here that gonna make it brighter? I'm a complete newb so if i gonna buy something without advice i probebly just gonna waste my money. Some sort of drop in would be nice but i also think i can manage putting some parts together.

since this does not look like aluminium you will not be able to run high powered leds...
maybe you should save your money for another project :devil:

Its all plastic but i can drill som holes and use a decent heatsink innside it. I see other people are doing that with dewalt/ryobi/makita stuf. I don't need it to run full power for hours. What i realy need is a shopping list for driver and led that goes to the 14,4v li-ion battery.

you could run 4 xp-g if you used a linear regulator based off of transistors or a lm317, maybe even power a fan

Ok which regulator? Links to wich parts and where to buy had been nice.

4x xp-g ? why 4