How do you adjust distributor timing for a c1500 pickup?

To adjust the distributor timing on a C1500 pickup, first ensure the engine is at the correct timing position, usually at top dead center (TDC) on the compression stroke for cylinder one. Loosen the distributor hold-down bolt slightly, then use a timing light to check the current timing against the manufacturer's specifications. Rotate the distributor slowly until the timing light indicates the correct timing mark on the harmonic balancer. Once adjusted, tighten the hold-down bolt and recheck the timing to ensure it remains accurate.