I can't help with dimensions, but Airstream has a fair amount of literature scanned and organized for the older trailers. Here is the layout of all the '72 trailers, but it's not true plan views, it's a more-or-less isometric 3d representation. Even in the years they offer true plan views they aren't dimensioned.
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— David
Zero Gravitas — 2017 Flying Cloud 26U | WBCCI# 15566
He has all of the virtues I dislike and none of the vices I admire. — Sir Winston Churchill
Hey Big Monkey!
I recently purchased a 2007 20' Safari SE and wanted to get a new mattress. Websites I searched wanted a template but one suggested requesting a schematic for Airstream. I went to the Airstream website and found the "contact us" tab and sent them a message asking for the schematic. Airstream quickly responded with schematic showing all dimensions of the forward bed all of the way down to the 1/10th of an inch. You may want to send them a message requesting the interior layout dimensions for your trailer.
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