From 1959 parts book
Wheel part # 3707064, lock ring # 2059902, application 3/4 ton, 1953-1955.
In GM Heritage Center info. Options for 1954 3/4 ton trucks. Option #282. 6.50X16 6 ply tires
RPO #282 16" wheels were only used on dual rear wheel equipped trucks & they did not use hubcaps.
These rims were somewhat common on the 1 ton trucks but...
I have never even seen a 1954 3/4 ton truck with factory dual rear wheels.... at best they were an obscure option on 3/4 tons.
The original question mentioned nothing about the truck having dual rear wheels so, RPO #282 would not apply to his original question.
From the GM resto pack for the 1954 trucks....
Only 15" & 17" wheels were offered on the standard 3/4 ton trucks.