I finally got the rest of the shop manuals that I wanted (they were free!, thanks to a good friend at a dealer. There a bit dirty, but still in good shape and I couldnt pass up the price

)
Anyways.
FRANKSnBEANS This is how you program the Keyless Entry for a 91 Caprice straight from the service manual. I have not got a chance to try it yet as I have been busy. If you need more help with it, I might be able to scan some of it from the manual.
One or two transmitters may be programmed. When 2 transmitters are to be programmed, they must be programmed during the same program sequence [see below procedure]
1. Open the luggage compartment lid. [Trunk]
2. Access the programming connector. [ In the diagram it appears to be on the left-hand side of the car in the trunk, is attached to the wiring that runs to the rear left lights, but is a small connector with only 2 terminals. If it is too unclear (I apologize for the bad description), pm me and ill try to scan it for ya.
3. Jumper the 2 terminals together using a fused jumper. The door locks and trunk solenoid will cycle indicating the reciever is in program mode.
4. Press any button on the transmitter (only once). The Keyless Entry Module will cycle all the Door Lock Motors and Trunk solenoid once. Any transmitter code that was previously programmed is now erased.
5. If a second transmitter is to be programmed, press any button on the second transmitter once. The Keyless Entry Module will cycle all the Door Lock Motors and Trunk solenoid once.
6. Remove the fused jumper from the Keyless Entry Programming Connector.
Enjoy
