I replaced my 2.8 motor with a 4.3 from a 93 S-10. I had to use the 93 harness for the engine. My problem lies where the wiring block goes thru the firewall. The pins from the 93 are in a different location than the ones on my 86. What I need is a wiring diagram that show the pin location of the wiring block for a 86 and 93 S-10. Anyone with an idea on where to find one??? I have check local Chevy dealers and they say they dont have anything on that old of trucks.

Thanks

How about a Hanes manual?

Did the 4.3 come out of a blazer if so you need to use the wiring harness from the 86 headlights the blazer light harness did not come through the firewall. I did a 1991 4.3 out of a blazer in to a 1993 s10 p/u and they changed the harness under the dash in 1992 had to add a wire for the fuel injectors to work, still can not get the speedo to work.