If your heater is just squeaking / squealing then there is a much easier cure than the dash out method ( = big job

)
Take grill off = 3 mins.
Take black plastic rain guard grill (above the rad) off = 3 mins
Drill a pilot hole were the grey dot is marked in this pic =
There is nothing behind the metal for miles around so not to worry about EXACT placement or how deep your drill goes when it breaks through.
Now make the hole as big as you can, I went up to about 3/4 inch with one of those tapered hole expanders on the drill. Again, no worries, make the hole as big as you want, bigger makes the job easier.
Now the tricky bit.
I soldered a 12V 21 Watt bulb onto a long bit of wire and connected it to the battery.
I dangled it in the void by hanging it through the big gap between the top of the metal panel and the bodywork. This a couple of inches above where you drilled the hole. Easier to see and feel for "in the flesh" than to write down or point out in the pic, You will figure it I am sure.
Now, if you look through the hole you drilled, the void will be well lit up by the light.
Now look up a bit and towards the dashboard.
After moving the bulb around a bit and adjusting you line of sight (it is higher up than you might imagine), you can see the end of the heater fan motor, along with the exposed bearing.
Next get an aerosol of you favourite grease, you will need to extend, by quite a lot, the little tube you clip onto the spray head. I used some of that hard black plastic "advance and retard" pipe that goes from the carb to the dizzy.
Now squirt it onto the bearing, perhaps with the fan running to aid penetration.
This is easier said than done, but you will manage I am sure ( I did

)
Best to try not to get too much grease everywhere as it will cause muck being drawn in by the fan to get stuck all over the place.
Now stick some masking tape over the hole, put the grills back on and away you go
btw, the clips on my splash guard grill (the smaller inner one) broke but I found 4 small tie wraps made a very neat alternative fastener.
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