I'm new so forgive my ignorance,lol. I predator hunt and have a couple of trust fire tr-3t6 flashlights. They work good for identification of predators at 100-150 yds, but only last 25 minutes or so then change batteries (18650's) Now my question, I have a nite lite that uses the old KRP 113 bulb and has a 6volt gel cel battery (4.5ah) Is there an upgrade bulb that is as bright or brighter than TR-3T6 that will work in this light? Or will I have to change to a different head to achieve this, hoping to get longer run times.