Personally, I would try to discover exactly why the vinyl wrinkled in the first place. Could it be heat from some source? If you you might think there would be more wrinkling that just this one spot.
The first thing to do when acquiring a vintage Airstream is to locate and stabilize (stop) all water leaks.
You don't want any of them continuing to damage your new baby!
For me, the next step was to put one of those paper school notebooks in the trailer to note any and all deficiencies and then...? Clean the whole interior to within an inch of its life! Even the darkest, dirtiest corners.
Why? By cleaning it, you will find each and every little thing that you will want to repair | fix | improve, before falling down the rabbit hole of chasing things that may or may not actually be important.
When you arrive at the end of your cleaning job, you will have a nice, clean trayla and a good long list of things to do. Take an hour or so to go through the list, and number each item as to the order in which you want to do them. Now re-write the list in order.
Start working on it, beginning with number 1!
People start large projects such as yours, and some wind up abandoning them because things get overwhelming. By planning it out, YOU will control the jobs, not your trailer.
ps: if you have a friend that knows lots about AS (Airstream) TTs, go through it with them, and see if they agree. One step further would be to get projected costs for all of the items. That way, you can plan out what speed you want to go through the TTD (Things To Do) list.