I remember my Brother’s 55 Buick had the starter in the accelerator pedal. When you pressed on the accelerator the starter was engaged. I guess it had some solenoid or something which disengaged after it started.
I also remember my Father’s pickup had a throttle. It was sort of an early cruise control except it simply kept the carburetor at the same amount of gas. There was nothing automatic about it. You had to push it back in if you stopped.
Willys Jeeps had throttle knobs too for running accessories using a rear wheel drive. On at least one I remember there was a warning label saying never use as cruise control.
My G’father’s (who raised me) 50-something pickup had the same throttle control pull-push knob. It worked good for cruising long distances on relatively flat terrain. Color me nostalgic....