I've got the 5 spoke 18" wheels on my range rover and am thinking of changing to 20" or 22" wheels. Will these fit without rubbing or will I need to make further mods before I can fit them?

Also booked in for tinted windows and chrome side steps.

Then plan to fit a PSI Digital Powerbox which is supposed to increase power and fuel economy.
is anyone else using this and are they any good?

There is space in the dash above the stereo and next to the clock which looks like it could hold a sat-nav screen. Anyone done this?

TIA.