It is a fairly common modification in Europe.
Either used 'as is'
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With the window(s) installed in the now fixed in place rolling doors
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Or the best way (IMO), with false walls directly behind the rolling doors so the aluminum doors can be down for travel and security and then up for camping
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They get it through the back door if you are wondering.
The downside to keeping the doors is the tracks for the roller have to hang down from the ceiling 6 inches, so you only have 55 inches of headroom. Some have countered that by lifting the whole box and installing a wall below the rolling doors, or in the case of that blue Iveco when it was in fire service the back was built that way, and the short 'wall' underneath the roll-up doors, swung down and made a platform to stand on for the firefighter to access their equipment.
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