I think Becky's right; you can find twins in almost every model of AS.
If you are buying a vintage one, you can get rear bathroom with mid twins (or one double with tons of cabinets), OR a mid-bath with rear twins.
If you want to look over what the vintage ones had for interiors, there are lots of great pictures on
this site. Just go down to the bottom and pick a model and year.
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“Courage is being scared to death, but saddling up anyway.”
...John Wayne...........................