Question about Leupold MX 331 flashlight

First post here... I just bought a brand new Leupold MX 331 at a retailer that got stuck with it in 2009 when the customer declined to purchase his special order. It is NIB and they even gave me three new SF batteries with it, in addition to the OEM batts in it. They told me to make an offer- I got it for $50! My question is, are there any upgrades I can do to it without modding, like a higher output LED, or a head with multiple LEDs? Or will I have to machine the head to fit a better LED assy? And is machining the tube for bigger batteries worth the effort? I think user "gswitter" has some experience with modding the Leupolds, but I'm new, so I can't PM him...

Thanks in advance!

you know your problem is common to anyone that makes the first ever mod of a flashlight.

Collective experience might help you but we need to see the flashlights dissasembled. Esepcially in the reflector/LED area
(I even haven't seen a pic of such a light from the front)

A safe bet is to change the LED to an XML....usually this LED works well in reflectors and has an up-to-date efficiency...
edit: researched a bit and i see they use a Cree XRE that cannot be higher than a Q5 bin.