I have been poking around more lately. I think this will do it as long as there is a decent way to wire it. The 70's style switch only has three posts, so I am not sure if can work and look good too?

THIS ONE HAS THE WIRE PIGTAIL AND A SWITCH

THIS SWITCH IS THE 70'S STYLE

And then get the side fill tank found here

1966 C-10 Step Side
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