Needing to time my 1993 Bravada

Note: let me know exactly where you find it on your model

Set parking brake, block drive wheels and place transmission in Neutral or Park. Warm engine to normal operating temperature. Turn A/C off (if equipped). Ensure Malfunction Indicator Light (MIL) is off.
Disconnect Tan/Black Electronic Spark Timing (EST) by-pass connector wire. On 4.3L, by-pass connector is on wiring harness conduit near distributor. On other models, by-pass connector is located near heater housing in passenger compartment. On all models, DO NOT disconnect 4-wire connector at distributor.
Connect timing light to No. 1 spark plug wire. Check timing and adjust if necessary. See V6 IGNITION TIMING table. Reconnect EST by-pass connector, and clear ECM trouble code.