Need some demolition advice. Neighbor burned out his Dewalt cordless (don't know how, but it's toast) so I thought I'd salvage the finger chuck. It's all held together with Torx screws, but I've got the right bits. The problem is once you get the case off, the drill was clearly built from back to front. So how is the chuck held on? I can see a hex shaped socket in the base of the chuck, but I totally wasted an Allen key trying to undo it. Did they swage it in after tightening? Whatever, how should I separate the chuck from the dead gearbox and motor?