My '57 LCF has electric wipers as that was original equipment for the big bolts. The knob on the dash has no electrical components, it is a cable from the knob that actuates the electric switch in the motor, all electrical components are integral to the motor. The 1/2 ton replacement motor might be different than mine.

1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy