Hand throttle. Push/Pull and I guess glove box "Chevrolet" script with Custom Cab. See pic of 1961 for both. Not mentioned in GM Information kit til 1964, as Throttle control/dealer installed accessories.
Also see 1960 Owners manual pic
Used for cold start, PTO, crawling in gear, 4X4 operation.......
Could have been added by owner
Still available as aftermarket
Attachments
Throttle cable.jpg (48.2 KB, 146 downloads)
throttle 1960.jpg (144.04 KB, 141 downloads)

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