IF the switch and connector had burnt wires an blown fuses, there has to be a reason.
Check the blower area to see if there is anything in there slowing down the blower, mine gets leaves in there sometimes.
if something is slowing the blower down then the resistance will increase causing extra heat, which in turn will burn wires, connectors and then your truck.
Check the blower while it is out and see if it turns free, apply 12 volts to it and see how it runs.
FIND THE REASON…