1954 had Thistle Gray painted hubcaps as standard equipment on 3100 trucks.

There was a Accessory full size stainless-steel wheel cover for those 1954 16' wheels.

1947-53 Chevrolet 3100 wheels had stainless steel hub caps (as standard equipment - no other RPO/accessory hub caps in those years).

Thistle Gray pertinent page (1953 and earlier) in Master parts book
Stainless Steel pertinent page (1954) in a Master Parts Book