1950's trucks were still considered as a utility vehicle. GM wanted these trucks to be as convenient as possible with low cost and hoped for big numbers in sales. The hand throttle is very useful for several needs as pointed out and added to the utility use of trucks in general. When they were manufacturing the steel dashboard it was/is cost effective to use as few different parts as possible to cover a wide range of vehicles, so the dashboard on your 1/2 ton is the same as the big bolts. I like the hand throttle in my '57. I wish my 2011 2500HD was as simple and reliable.

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