Disconnect the cable from the negative battery terminal and unplug the electrical connectors from the distributor. Remove the cap from the number one cylinder spark plug wire terminal on the distributor. Turn the engine until the rotor points towards the spark plug terminal. Mark the distributor base, rotor tip, and cylinder head for alignment. Loosen the distributor collar bolts and remove the hold-down bolt. Pull out the distributor carefully. To reinstall, align the coupling's grooved tang with the housing protrusion if the crankshaft was turned. If not, insert the distributor as before. Check alignment marks and rotor position, loosely install the hold-down bolt. Reverse the steps to complete installation and check ignition timing before tightening the bolt.