you can get factory wiring diagrams for free at http://phatg20.net/. just register and log in. good luck
You might try the public library. They have amazing stuff. I found a wiring diagram for a 56 Chevy at mine! All the best!
you might try www.haynes.com
The spark plug wiring diagram for a 1994 Chevy Cavalier can be found in a service manual. The manual might be available at your library, or can be bought from most any auto parts store.
what are you looking for? I have 5016 book. Might have diagram
http://www.1957-chevrolet-alternator-conversion.com/wiring.html you might be able to find it here
I was wondering if you might be able to send me the wiring diagram for a 1994 pro 20s bed? Thank You Martha Ray
google it. there are a lot of magazines on your truck that might also have a diagram!
This might be available in your users manual. If you are not able to find it there, do a quick image search for the diagram.
If you want a free diagram, the best bet is your local library to check out a manual on your truck. You might be able to copy the info you need there. Free wiring diagrams are rare otherwise because they are information mechanics pay good money for.
you might try www.haynes.com
http://www.veryuseful.com/mustang/tech/engine/
The headlight wiring diagram for a 91 Dodge shadow can be found in the service repair manual. The manual might be found at the library, and can be ordered through most auto parts.