Yep, I've seen both 'solid' wheels and spoked. Cutting out the covers won't be a major problem, but mounting the wheel could be, if the kit doesn't include the actual gear leg. My kit is the Italeri version, courtesy of Glenn (I think the ex-Hawk/Testors kit), which uses pins inside the two halves of the spats. The bar you mean acts as a 'mud scraper', and I think also an attachment point for the covers.