What I've tried and what works well for me is mounting the wheel cover by drilling out the top of the acorn lug nuts and epoxying a smaller nut inside ... see my signature for the link to my How To for Simple Civic VX Wheel Covers (the VX comes with alloy wheels too). It does "deface" the lug nuts, but those are relatively cheap to replace.
I used a plastic serving tray, but the principle ought to work the same for the pizza pans (?) you have.
If it were me I'd just find some steel wheels that fit (as small as possible for best FE) and then use the hubcap style racing disks or fiberglass up some cheap hubcaps from the salvage yard or auto parts store.