When replacing your 4Runner's A/C compressor, you can't allow any refrigerant to escape into the atmosphere: refrigerant is a pollutant and the law requires that a professional recover the refrigerant in your A/C before removal.
Take the 4Runner to an automotive facility and ask for them to recover the refrigerant in your A/C system.
Once you have the 4Runner back home, remove the feed and return lines from the A/C compressor with a ratchet; each line is held on by two bolts.
Loosen the A/C compressor belt lock bolt with a ratchet and loosen the belt tensioner until the belt is loose enough to remove. Toyota engines use multiple drive belts rather than a serpentine belt, so each belt must be removed separately with its own lock bolt and tensioner.
Loosen the A/C compressor mounting bolts with a ratchet to remove the belt and compressor.
