Well I guess that changes everything.
This will be a great way to unload a ton of guilt that you've been carrying for a while.
If you simply google "Airstream Liner" you will come across a ton of information and images regarding your trailer. There are lots of people on this forum who will be able to answer all of your questions.
The best thing about these early trailers is their simplicity. There was very little to them other than the sink/stove cabinet, a closet, and a couple of overhead cabinets. Looks like the original hardware is intact. From the photos, it appears that some things have been added. The white paint and corrugated bulkheads are not stock. Hopefully nothing original has been removed. Once you get those end windows fixed up, it will look even better. You might want to forget the polishing part all together and retain that natural "patina".
You've got a great project ahead. Glad you're keeping it. I'll be rooting for you!
Charly