The next step was putting the clamping waterproof nut on the 3/4" mount, ensuring that it was centered in the hole.
In the below picture, you can see the 1/2" braid coming out of the hole directly below the 3/4" hole and NMO mount. You can also see the coax coming out from inside the brace.
I was trying to think of some material to use to attach the ground/radial braid and the copper tape that I was going to use for the radials. One of the members of the Brain tRust suggest cutting about a 2" piece off of some copper pipe, cutting it down the middle and then flattening it out to make a flat plate. That worked out great. I drilled a 5/16" hole in the center of the copper plate and ran the ground braid through the hole. I ended up attaching the ground braid to the plate using 2 screws with star washers and flat washers. I wanted to solder it but it was taking too much heat to heat the plate and the braid.
Next, I cut 8 pieces of the copper tape (Amazon.com: Ranger Memory Glass Foil Tape 1/4 Inch 15 Feet Per Roll, Copper: Arts, Crafts & Sewing
) Each piece ended up being about 21" long. This is fine since in theory, each radial needs to be "at least" 1/4 wavelength long, which would be about 19 1/2". This tape has a sticky side on it and it stuck to the inside of the roof very well.
I then reinstalled the hot head liners.
To be continued......