I would look at the spartan interior groups from the commercial lines like Vans and small HD trucks. They usually have bare minimum interiors. But then again, I'm thinking A-100 vans and such.

I think the new Drag pack Hellcats have a good compromise with bareness.
As far as trucks, perhaps peeping some of the Nascar truck series interiors.
I love the bare, black electric tapped steering wheels from the Fireball Roberts days.