The caliper screw should only have a little bit of torque on it...~12 ft-lbs IIRC. Some anti-sieze would be a good idea to. Just did rotors all around, and I made sure to put a thin layer of anti-sieze on the hub faces before mounting the rotors, and also on the rotors before mounting the wheels. Making sure that the hub surface is abolutely clean with no corrosion or unever surface is very important.

Cheers,
Duey


p.s. if I had stripped the original grub screw, I think I'd be tapping out the original and retorfitting another one...although it's not going to go anywhere without the caliper slider assembly removed...