As well as the other issues already discussed, there are at least two other points to be considered. The existing windows may very well have to be removed and repositioned, a fairly formidable job, when one considers what that really means.
Also, the majority of the roof vents will also need to find new homes. Lots of cutting and patching are involved in these two jobs.
IMHO. If the current layout is really a problem for you, I would put it to you that selling the AS you are currentky working on and purchasing another unit would be cheaper and more importantly, faster.
You don't really want to make working on a trailer your lifes work do you? Camping is ever so much more fun.
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“Courage is being scared to death, but saddling up anyway.”
...John Wayne...........................