The rotors should either be turned or replaced when you install new pads to ensure good contact with the rotor. The job is simple... really simple. Do the following for each side:1. Jack up car, remove wheel.2. Remove lower bolt on caliper. (one bolt only)3. Rotate caliper up and off old pads.4. Remove old pads5. Lower the calper.6. Remove the two caliper bracket mounting bolts.7. Remove the caliper assembly from the rotor and hang from the top suspension with coat hanger wire. Do not allow it's weight to hang by the rubber hydraulic line!8. With an impact driver, remove the two phillips head rotor retaining screws.9. Remove the rotor take to machine shop or replace.10. Install machined old rotor or new rotor. One solid whack on the impact driver to secure the phillips head screws is all that is needed.11. Reinstall the caliper assembly over the rotor and torque the two bolts to spec (~80 ft.lbs).12. rotate the caliper up.13. With a C clamp and the old inner pad, press caliper piston fully into caliper. (beware: this will push brake fluid back into the reservoir so be sure you don't overflow the reservoir!)14. Install the new brake pads.12. Lower the caliper onto the new pads.13. Tighten the lower caliper bolt to spec (~36 ft. lbs)14. Press the brake to push brake fluid into the caliper and press the new pads against the rotor. Brake pedal should go to the floor a coupld of times but then go firm.15. Install wheel/tire and torque lug nuts to 80 ft. lbs.16. Top off brake fluid as needed.With the proper tools at hand and a little experience, you will find that both sides can be done in less than an hour. The machine shop will generally take the rotors overnight unless you get them in early.Putting new pads on an old rotor is a bad idea since both parts wear in together and may no longer be flat. A new pad is flat and may have a small contact patch on an old rotor. Having the old rotors turned at a machine shop ensures you have full contact with the new pads. A new rotor is already flat and these days is a cheap alternative to having them turned.Get the associated Helm Service manual!
www.helminc.comGood luck!