I guess that for you Opportunity also hovered slightly on the surface, right? I see.
When I placed Spirit and Oppy on their final positions, I used as reference the HD map of Mars available as a free DLC, which has more high quality bump maps than the textures of Mars distributed with the program. Nobody else mentioned this until now, thanks. Either they all have installed HD textures of Mars, or they didn't care to mention this discrepancy.
Anyway, I'm afraid you'll have to download HD Mars textures DLC in order to see the rovers as intended, I'll add this info in the description as well as add HD Mars textures as required DLC.

Idk if anyone else has told u this, but for some reason the spirit rover is underground on mars and I can't see it. Can u possibly fix it?

"My battery is low, and it's getting dark.."