On the V36 you swap out the whole unit and get a large vertical screen, a unit that just does the screen at the top, or you can swap out and get a replacement Aus unit to replace the Jap one (no car play/andriod auto) still keeping the Jap buttons.
The cameras can be upgraded to one rear HD cam but you loss all others. Its a dumb system that puts all feeds into one input for video, and these upgraded units only seem to have one video input in them too.