This cabin had a removable seat infill like those fitted in Fo'c'sle’s. The problem with that was, when used as a seat the bed was only 12” inches wide??
This article explains how the whole cabin was rebuilt into a double cabin with an actual increase in storage space and the addition of a hanging locker.
1937 words 10 pictures. Price for this article $10
REMODELING A SMALL CABIN