I'd used a hubcap on side-mount spare-tire.
I will use the 1954/55st truck full wheel covers
] on my "deluxe" pickup. I was very lucky to find/buy 5 wheel-covers several years ago.
I'll try to remember to check the original box to see if I bought a box of 5 or a box of four plus an extra one.
My guess is that a 54/55st buyer of the side-mount spare-tire would have to buy an extra hubcap.
You 54/55st purists : check the stainless steel "button" on the accessory lighter in the image linked-to above (the lighter button did not match the black/white 54/55st dash knobs' buttons).
All the 54/55st after-market lighter buttons match the other black/white buttons.