If you cant find the door lock/unlock wires under the dash or at driver kick panel...save some time searchin and run two wires into the drivers door and tap the wires from the power lock/unlock button

Sounds like a lot more work, taking apart the door panel an everyting but it'll take more work and TIME to try finding it where its "suppose" to be

other than that...everything else on the 91 should be ok to find