Before you start you need to get your AC drained by a certified AC shop. These old birds are filled with R12, which is toxic and very prohibited, at least where I live so don't do anything stupid. Or "smart", as I would have called it.


Start by disconnecting the battery, and drain the coolant. Remove the dash top cover, and the lower part of the dashboard. Center consol should be removed for better room. To pull the gear selector handle it's easier to set the gear lever in 1/2 or 3, and pull the handle backwards, in stead of upwards.


The dashboard is attached with 4 screws towards the windshield. Two at the center, and one at each side.


Behind the kick panel you'll find one bolt at each side. Now the entire dashboard is loose.


I attached jackstraps to the dash and hoisted it upwards in the sunshade attachment points.


Remove the fan. In addition, there are 3 heater box attachments, marked with arrows. While you are here, disconnect coolant hoses from heater core, and disconnect AC evaporator.


Remove these two screws. Disconnect all wires from the heater box, and the vacuum line from the recirc air diaphragm.


Remove the heater selector wire from the blend door rod. There is a bracket holding the AC part together with the heater part. Marked with arrow. Remove the bracket.


Approximately straight up from the heater blend door rod you'll find this screw. In addition, there is a plastic ribbon holding the AC part and the heater part together. Cut the ribbon and discard.


Caution! The heater box is still attached to the firewall by two screws conveniently placed just behind the engine! It's better to leave them and split the heater box from the AC part. Carefully pry the AC part out from under the dashboard, leaving the heater part in place. Once the AC part is out, you can remove the heater core attached by two screws.


Insert the new heater core. Make sure to replace any insulating foam where in poor shape. I only attached the upper bolt of the new heater core as the lower was only attached to foam originally.


Pull the lid of the AC part, and pull out the old evaporator.


Now the old evaporator had a temp sensor probe pushed into the core. As my new evaporator was of a different design I had to improvise: I let the probe enter the AC housing at the same point, then I bent it around the evaporator and inserted the tip into the evaporator between the cooling fins, stopping approx in the center ov the evaporator.


Mount the lid, and lift the AC-part in under the dash again. Put your hand in through the firewall via the fan housing, and pull the AC-part into position. Then it is easier to allign the heater box pin bolts through the firewall correctly. Mount the nuts on the pin bolts by hand, just keeping the AC-part around its position.


Enter the cabin again, and push the AC-part up and in, until you get this bolt attached. Use this bolt to pull the AC-part in place while you guide it with your other hand. Now you can fasten the nuts holding the heater box in the engine compartment, then you can attach all electrical connectors and the vacuum line from the recirc air diaphragm and the wire for temp control. Lift the dash back into place, and mount all screws. Mont the cooling fan in the engine compartment. Attach AC evaporator and coolant hoses. Fill system with coolant, attach battery and start her up. Check that all electronics are working, and no leaks. If everything is up to speed, you can mount the dash top cover, the lower part of the dashboard and the center consol. Take her for a spin, and check everything once more.

Now if you want your AC up and running again, you'll have to replace the drier, and replace the oil in the AC compressor. Rebuild the system with plugs for R134a and have it pressure tested. Then have your local certified AC-shop fill her up.