This link does a pretty good job of explaining what's typically involved:
Yahoo! Video Detail for 92 Ford Ranger 4X4 Front Brakes / Rotors/ / Bea...
It's a fun, easy job. Remove the master cylinder reservoir cap, prior to trying to spread the brake pads. Clean the old bearings with kerosene or Stoddard Solvent. Afterwards, it's fine to blow the old bearings off with compressed air--just don't spin the bearing. I would repack the wheel bearings with full synthetic wheel bearing grease (e.g. Mobil 1, Valvoline SynPower, or Amsoil GLC). This will provide better protection and gas mileage (less friction), which is important on 4x4s. The job goes easier if you use a pair of Lisle LIS44900, MAC P22A, or Craftsman P4735 Lock Ring Pliers to remove the C-clip. Get the torque specs for your truck.