It's great you have come up with a new blower motor switch connector replacement, but if you have a dragging blower motor pulling more amps than it's supposed to it's just a matter of time before something in the blower motor speed control circuitry smokes again. The factory wiring is undersized and can't handle any amp overloads throughout the circuit. An excellent way to permanently prevent this is to replace the dragging blower motor with a new one that doesn't draw excess amperage, then add relays to the individual motor windings controlling the motor RPMs.
HERE's one way to do it, although I would use a 4-way mini relay box under the dash similar to the below to keep it neat and compact.