best setup non staggered model x

HI. I have been considering replacing the tyres on my Model X 75D. There are a few options: 1. slap on the 21s from my Model S. I would like to get all 4s on 265/40 R21 tyres (i.e. non-staggered). Anyone did that? 2. replace the tyres on the current rims (which I think are staggered rims. Car...