The circulating fan switch has two wires. One goes the the large dropping resistor on the rt side of the heater/AC box near the passenger's left knee, then to the fan motor. The other goes directly to the fan. One or the other of the wires is shorted to ground. It doesn't appear possible, but the fan motor complete with the plastic impellers CAN be removed without pulling the dash. 'Taint easy but it can be done, even by guys with big hands.
As for the wiper motor, nothing new since 1974; its still a Jaguar unit & is rebuildable. I'd call all the vendors & check if they have a good used one in stock.
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