Thanks for the pictures in your gallery. The body is in nice shape! Swamp cooler? That's interesting....
Weight could become an issue. You would want to pay some attention to the approximate amount of materials in an original Airstream as you consider fitting out your Cruiser. I'd take it to a truck scale the way it is. I think your rebuild could reasonably increase the weight by one or two hundred pounds over original dry weight but you'd still need to keep an eye on how you camp (just like the rest of us!).
A good member by the name of Sugarfoot posted the weight chart
a couple weeks back. It doesn't give the GVWR (subtract the dry weight from GVWR and you'd have the net carrying capacity). The frames were lighter in those days but a rough guess might be that an additional 800 pounds is in the ballpark. I don't know if Airstream put that info in the manuals back then -- it could be worth seeing if we can find a member who still has a manual from that era.