Just measure how long you need them and go from there.you can use the bed strips for pickup,painted or stainless steel.i would start out by checking the lengths of the 47-55.1 3100 3600 3800 bed strips.
jim carter,classic parts of america,lmc,etc will have them. I'd use stainless steel carriage bolts as well.

Tim

1951 3100 Chevrolet
1951 Chevrolet Suburban Carryall
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