Wonderful as they are these long awaited mk2as are too low. I have set my layout board at eye level when seated (fed up being in a virtual helicopter)!
Everything is fine until the roof. As you say one or other is too thick. Perhaps it’s the MK1 as the roof is a separate part?
Anyhow. I made little wire horseshoes that fit under the bogies that raise the coach by just over half a millimetre. What a difference. How can the eye detect this????!

On another topic. Do you find Farish locomotives take the joints in kato unitrack
rather badly. I’m thinking of getting a file out to those rail ends.

I have pictures of my coach mod if you are interested?