The center cap included with the wheel tapers to a cone to quickly from the mounting point to the wheels . So I just left them off and kept the bearing caps on. I suspect new center caps could be 3D printed or machined though the tolerance is tight. If they came out straight for an other inch then transition to cone they would probably work but tight.
Not sure if i have a different hub or what, but mine don’t have the black rubber boot just a stainless cap that has the zerk behind it, that being said i think they look great without the caps even though I wouldn’t mind if the cap actually fit! They are a Good looking cap but oh well.
(215/65r17) on mine