Can any one tell me where I can find the signal wire to connect to a Sun tach or where I can find a wireing dia to show me where to connect.
Thank you

 

Moved to correct forum.

 

Diesel, CNG, or Gas? Which engine?

On gas engines, it should be the white with pink stripe wire coming off the PCM, which is in the engine compartment on the drivers side. On diesel engines (not sure about cutaway) there is a wire labeled 'CTO test output' near the brake cylinder that should have what you are looking for. Depending on how the cutaway body was modified, it may be inside near the parking brake pedal. There is a white/pink wire in the steering column, this is not a tach, this is the starter wire and will destroy your tachometer if you connect to it. Use a voltmeter to ensure your located wire doesn't output 12v when running or starting the engine.

 

Check under the hood for this:



As 95e150CW says its typically on driver's side, just above the master cylinder and white/pink in color. Mine was tucked away inside the wire chase running from side to side just under the cowl panel front edge.