Is my '94 EB pre-wired for the factory alarm and keyless entry modules? I recently picked up a couple of used modules from a salvage yard, but I can't locate the wiring harnesses. I had heard that these were also dealer-installed options, so I expected to be able to plug-and-chug

 

Could be, try looking here.

Green- Programming Connector
Blue- Keyless Entry Module
Red- Back side of cubby hole
big black thing to right of red circle- custom mod.

 

If you got OE stuff, it won't plug in. The dealer stuff needs additional dash wiring. The OE module plugs into a special OE RKE dash harness.