I tried out a 64bit Gentoo image for Raspberry Pi... This is very Gentoo. The Rapberry Pi 3B+ has a 64bit processor, but 32 interface to, like, everything. Basicially no one runs a 64bit OS on the Raspberry Pi, but you could, and if you use Gentoo and you can do something, well why not?!
It ran very fast for a couple of minutes, then it crashed.
I went back to Raspbian, and ran into a problem. One of my Raspbian images was running an updated kernel, that did not have anything in /lib/modules that matched. So I was unable to update the WiFi drivers. I found an article with the correct command to reinstall the Raspbian Kernel:
sudo apt-get install --reinstall raspberrypi-bootloader raspberrypi-kernel
So play time over and annoying problem accomplished I moved on to thinking about how to actually implement the bridge. I think I'm going to setup two RaspberryPi's to make this bridge. That will allow it to be more portable, and might make creating a educational guide for others to learn from easier. (The alternative being to use the RPi access point that I already have as an end point.)
L2TPv3 (Layer 2 Tunneling Protocol Version 3) seems to be the key piece of technology that I need to make this work. :-) I found NetworkLesons.com that has a very succieient explination of L2TPv3. While Wikipedia's L2TPv3 entry has some interesting history.