Try looking at the "vintage Airstream photo archives"
http://vintageairstream.com/photo-archives/. We used it to find photos of a similar AS to ours with a layout we liked and could work with. We then used cardboard box mock ups and painters tape to lay out our trailer, and adjust for what we wanted. It gave us a good working model to use. We still did a lot of adjustments as we built out the interior of the trailer, and we didn't essentially change placement of major weight pieces because they fit our model. That helped us with weight distribution.
And, yes, we agree with Islandtrader that you should do lots of reading on other's rebuild threads. It helped us immensely in our journey. Take pictures along the way as you build (and what you start with). Later, it will help you if you have to problem solve something that's not quite right, or help answer someone else's questions about how you did something!
Good luck! Post pictures!
Kay