[scoutinkeith]

I had to replace the heater core on my 93 this past summer, it's really not that hard to do. mine didn't have AC though, so if yours dose, it may be a little different.

first, you'll want to drain the antifreeze, then disconnect the two hoses that attatch to the heater core on the engine side of the fire wall.

then, take off the 4 nuts (again on the engine side of the firewall) that hold the heater box to the fire wall.

once the 4 nuts are off, go inside, under thedash, and disconnect the electrical plug for the fan, and the cables for the flapper doors.

once everything is disconnected, pull the heater box(plenum), it may be a little tricky, you'll probably have to "rotate" it down as you pull it away from the firewall.

with the heater box out, you will see a metal plate on the back side(the side that was towards the firewall. remove all the screws from the metal plate, and remove it from the plastic part of the box. if I'm remembering correctly, the heater core is attatched to the metal plate with two screws/bolts, remove those, and swap heater cores, then reassemble everything.

once it's all back together, fill it back up with coolant. also, to make sure that you get all the air out of the system(it helps if it's parked with the front a little higher than the rear) , leave the radiator cap off, and start the engine, and let it get up to temperature. watch the leval of coolant in the radiator, and as it goes down, add more coolant untill the engine is up to temp(thermostat opens) and the coolant leval stops dropping.

give me a few minutes to find it, but I think I have a drawing that shows the location of the 4 nuts that you have to remove.