I am attempting to replace the brake pads myself and save $120 (2 hours of labor). I have all the diagrams and instructions and stuff. However, I cannot remove the screws to the brake caliper encasing. I used WD-40, and I am going to try letting it sit overnight. I have also used a couple of different sized wrenches in an attempt to take the screws off (the wrenches keep slipping). Does anyone have any suggestions for getting those damn screws off (one that doesn't take a lot of $$$$)? Thanks.