My 51 3600 did not have disconnects on the heater motor. Removal or the heater takes 3 firewall nuts, two hose clamps and 2 defroster hoses. Disassembly of the heater is not difficult. I suspect you will find the wire inside the heater in better condition in case you wish to splice. Otherwise you may want to purchase a new motor.
Steering wheel; remove big chrome horn button, nut, washers and use a wheel puller. Column does not need to be puller apart. Don;t just yank your old wire out, tape the new wire to the old wire and use the old wire to pull the new wire through, I would do this from below dash to steering wheel end to avoid a splice.
Hope this helps
Mike
