Chevrolet Repair: Timing on 1990 Chevy K-Series 1/2 ton, control ic, timing light

Question
I am looking for the degree setting for a 1990 Chevy 1/2 ton with 350. I also need to know where the diagnostic plug is that needs to be unplugged to take the computer out of the loop so i can use my timing light. Can you help? Thanks.

Answer
I said brown with white stripe.
Actually, Disconnect the Ignition Control (IC) system by disengaging the "set timing connector". This is a single wire sealed connector that has a tan with BLACK stripe lead. This wire comes out of the wiring harness below the heater case

Go here.  http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/0...