What? You mean all 3 of them?
The silver switch on the top of the dash by the windshield is the windshield wiper switch.
The only other knobs on the dash (besides the radio controls if you have one) are the choke knob and throttle knob. Choke is on top and Throttle is on bottom to the left of the radio and above the ignition switch.
The throttle is sort of a primitive cruise control to keep the engine at a certain rpm while running farm equipment or using the truck as a harvester or something so that the driver didn't have to keep his foot on the gas. Also useful in winter to bring idle up while warming the truck without having to sit in the cab with your foot on the gas.
Do you have a factory shop manual? They are plentiful on ebay for $15 - $30 for original used ones.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
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