Obviously, there's lots of MK1 diagrams and I needed one that was with the same window and door positions. I decided that Diagram146/147 would suffice. This has some different interior bits but the outside positions for everything, including the toilet windows, is the same (close enough anyway). No doubt, someone will disagree with this!
At this point I decided that I might want to revert to the original coach, with the open arrangement. For this reason I decided to make the modification reversible.
I achieved this and I'll explain how this was done and also describe the module required to create the corridor arrangement either later-on here, or in the Newsletter. There's also the possibility that others might to modify their coaches, so I could provide the module parts to make the same change. I'll also add some photos.