Oh dear, I think you were looking at someone else's YT videos. I'm way too self conscious to do that in front of this experienced crowd.
I'm worried people will see what I'm doing and boot me from the board!
But what you descibe sounds intriguing. If you find out whose vids you were watching, could you post it? Sounds like something I could learn from. Dowels sounds smarter, but because of the size, I'm using 1/2" aluminum square tube for framing (light but strong, hopefully), and attaching 1" foam boards on either side of the frame. Tests have been successful, and believe it or not, I've had good success using TBII to attach panels. Way cheaper than GG, of course, and once you wrap it all in cloth, glue and paint it, I was thinking I didn't need to worry so much about its longevity. But maybe I should. Hmm...
JazzVinyl, I finally decided on 8' 2". Given what the focus of this board is, I realize this experiment is way way too big and wide. But it's all a crazy experiment, drawn both from other people's experiences here, and my wild imagination that's not informed by that experience!
Hopefully, people here will at least find it amusing. Someone here pointed out that some states include "equipment" in the legally exceptable width so I'll be able to put lights, door handles and such on.