How do I change the chuck on DwWalt DC728 driver?

I want to add a point of clarification, that when I "cut the chuck off" it was just the tip end to get to the locking screw.

Reg
March 2010

I figured it out myself and am posting the answer here. I went to:

http://www.ereplacementparts.com/dewalt-dc728-type-144v-cordless-drill-parts-c-1009_1162_2861.html?keywords_category=DeWalt%20DC728

There I found the "exploded" view of the whole drill and therefore the details of the answer. With a Milwakee SawsAll I cut the chuck off after removing (destroying) the chuck by taking out the three drill bit grips. That way I could get to the star (not Allen) head lock-screw. It was easily removed by clockwise turn after mild heating to lossen the factory applied "Lock Tight". Then I locked the motor on the "drill" setting and tried to unscrew the chuck fastened tightly in my bench vise. I applied pressure to the drill body until it creaked. No go. So I took a torch and heated up the chuck remnant directing the heat away from the plastic drill--not too hot now. When it cooled down a bit, with scarry hard counter clock wise pressure on the body of the drill, it popped and unscrewed! Smiles! Now I have to find a replacement chuck! Hope this helps someone!

Reg
March 2010