How much of your boat do you have to dismantle to perform an engine(s) service?

[Vanilla]

I heard that when Halberg-Rassy adopted a new engine for their 36' model, which had the service items on the other side, they flipped the whole accommodation plan of the boat so that the cavernous "engine room" doors in the walkthrough opened onto the correct side.

Pete

The other sensible thing Hallberg Rassy does is fit the engine and tanks after constructing the hull so it's possible to remove and replace these items via the companionway without having to take the boat apart.