[Rascal M]

My 66 mustang coupe orginally came from factory with a 6 cylinder and i've upgraded it to a 351 windsor. Question is, will the wiring harness from the 6 cylinder work with the 351? I can't get the solenoid to kick in when I turn the ignition switch to start. I can cross over the solenoid with a screwdriver and it will crank the engine. I have the wiring diagram but unable to figue it out.

TIA
Glenn.

[Blade10]

Yes the harness will work.

My Guess is that you probably forgot to plug in the two connectors on the right hand (drivers side) of the firewall or you might have reversed them. They each have 2 wires and can be reversed. One of the connectors is the reverse lights, the other is the starter circuit. (Im trying to explain you can plug the start circuit into the reverse lights and vice versa, hope what I mean is clear.)

If you get lost PM me and Ill send you a picture of the connectors I am talking about.

Blade

[Rascal M]

Thanks Blade, I finally figured out the problem. It was the neutral safety switch. My understanding was that this mustang came from factory with a 3 speed manual and it wouldn't have this switch. Well I guess somewhere along the way someone installed a different wiring harness. The 351 fired up without a bit of trouble after crossing over the safety switch.