I must admit I have been thinking about whether FELD would actually put Lupe back into El Toro, and I think they probably wouldn't. Let's face it there are a bunch of other drivers for El Toro but there really has only ever been one main driver (McDonald) same thing with (to less extent) Max-D and Grave Digger are two that come to mind. FELD I can't see having two main drivers for El Toro, nor can I see them bumping Marc out of his position as the "Most Famous" El Toro driver. Plus that may run into problems with the World Finals, yes they could put Marc into a different truck just for Vegas. But I don't see that happening being that Marc has the black El Toro.
However, they have been advertising the other El Toros as Orange, so maybe their coming out with a new red El Toro? After all they did advertise (at least for the first quarter) last year that Chucks, Aarons, etc. were Red. Then Lupe would hop into the Red one.