My dashboard removal steps were as follows:
A) Remove the three main instrument clusters as well as the centre guage pack.I suggest you tag the wires to make it easy to re-connect them.
B) If you have a Tropic-Aire system you must first remove the plastic cover over this unit which hangs down under the glove compartment.Panel is held on by two screws,one on the right-side kick panel and one into the heater box enclosure.Next there are two small bolts which fasten up into the glove compartment.Remove these and the aux.cooler will drop down.If you don't have Tropic-Aire you're on your own ? I assume the parcel shelf would have to be removed.
C) Remove the two screws which attach the heater box console to the dash.
D) Remove the two defrost swivel vents on top of the dash (These pull out with a good tug).Once you have these out you'll see two of the bolts which attach the dash to the firewall/front cowl.I believe they're 12 or 13 mm.Remove these bolts.
C) Under the dash there are the two remaining dash bolts.One is above and to the left of the fuse panel and has a bunch of important ground wires attached.Tag these so you don't miss any on re-assembly.The other bolt is on the right side above the L-Jet computer box.
D) There are a couple of relays which are attached to the dash frame to the left of the steering wheel.Lie on your back and using a good light look up and you'll see them.These need to be removed from their attachment points but their wiring can be left alone.
E) You can now wiggle the dash out of its position and manouver it out.The vent hoses for the outer eyeball vents will still be attached but will pull off as you yank the dash out.The steering wheel does not have to be removed but should be placed in its lowest position.
Now you have open access to all the wonderfull stuff that has been sitting under your dash for 20 years rotting and overheating.! You've earned the right to guzzle some beer or wine while you carefully inspect all the connectors for signs of trouble.Remember don't look anywhere near the heater valve because it will instantly start to leak
I recommend that you check the dash mounting brackets while you have it out.These things are held on with rivets which loosen over time and allow the dash to move around and squeek.I gave mine a shot with the MIG welder and they are rock-solid.
Once you're at this point removal of the heater fan motor should straightforward but if you have any questions feel free to ask.