Glad you found those bulkhead feeds ok, Bruce.
That's a very good panel. Just depends on what you want or what you expect it to do. It'll give you a couple of amps per hour during that part of the day when the sun is pretty high, say 10 or 12 amps a day or so.
If you've got room, more would be better. I'm early on in the restoration of my Caravanner, but we've had solar on the boat for a long time and most of that system will move to the trailer at some point. We've got 250 watts spread over 5 panels and it lets us pretty well run whatever we want. I know I won't have room for all those panels on the Airstream, but I'll try to mount as much as I can.
Best thing is to try to develop a budget for how many amps you use on an average day. Add up each 12 volt
device you use and multiply its amp draw by the hours a day you use it and get a total for everything. Then you'll get a pretty good idea of how much solar you'd like to have.