Was just reading thru the step by step TPS mod by coombest (which I reckon is a TOP NOTCH effort - well done mate!) and thought that I'd offer this little tip for dealing with soft-headed fasteners such as encountered here. Use a bit of valve grinding paste (a cheap alternative to proper "screw grab" stuff) on the tip of your Torx bit to give a more positive grip in the recess. Should go a long way to preventing the tip from munting the screw.
Me gonna do this mod very soon me thinks
