Another bed switch
No, I have not done what you have done, but something similar. I took out the two twin beds in my rear bedroom model 31' Excella, and installed a king size bed sideways. It took two big gorillas to get the king mattress in their but we did it. So your plan is just as bold but easier. What you can imagine you can do (to parapharse Henry J. Kaiser....).
Good luck with your project.
1984 31' Excella, mid bath, king size bed
1998 Chevrolet Suburban K2500, 7.4L/454 c.i., 4WD, Pullrite Hitch
AIR No. 2375
"You know... life is just the way it is...."