I installed an aftermarket unit on my '92 EB and it went in an access panel
that is located in the front on the passenger side just in front of the
door, down where the feet go.  It's like vinyl trim.  If I recall correctly
you need to remove a screw or two from the trim to get it off.  It might be
in the same place on yours.  I also added a relay to control the interior
lights--they stay on for 20 seconds when the doors are unlocked.

If it's like mine then you could disconnect the remote unit and plug the
connectors back together and not have a remote any more if your problem
cannot be resolved.

One thing that comes to mind that I had happen to me.
1. check your truck's battery voltage. I had flaky operation of my '94
remote when the battery was signalling me that it was about to die. It
did strange things such as you describe and then a month later left me
stranded in a parking lot.

BTW, I dont believe the '94 had a factory installed alarm. It was
dealer installed and is a model VSS-600 Plus alarm unit.  Thats why
its not in the owners manual.  Do a google search on that number or go
to your dealer and see if he has a unit. Its not cheap, when I
replaced mine it cost me $250.

Its located in the drivers side kick panel right by your left foot.
(at least mine was)

Oh,  one more thing, If you're handy with a soldering iron, the reason
why mine died is because the main cable connector is a big long nylon
strip with embedded pins soldered into the circuit board.  Over the
years the differing thermal expansion rates of the nylon and the PC
board itself caused every single solder joint of that connector to
fracture. All I had to do was resolder the connector pins and it
worked like a charm. I didnt need to spend $250.

dickm