I AM DONE!
THE X-MTMs ARE FINISHED!At least as much as I plan to do. I may do some sort of covering for the drivers and ports. But not thinking of that now.
The last thing I had to do was to make a base for these. They are top heavy and on carpet they are tippy. And my floors in my old house are less than perfectly level.
Here is what they look like

The stands are perfect, IMHO...

The stands started out as a layout on my work bench. It was the only place large enough to be able to make the radii that these used.

Have you ever seen one of these?

I picked them up from a used tool store that we used to have around here.
I add a pencil to one pointer using some Loctight blued gummy stuff.

I used this to layout the large radii for the sides of the bases. Once I had the whole thing laid out on the workbench to my satisfaction I transferred it over to a plywood template. The template also had holes drilled in it for where the mounting screws and the leveling knobs/screws are to go.
The outline of the template was traced onto some vernier finished 3/4” plywood and the holes were transferred to the plywood by drilling to just a shallow depth. After the pieces were cut from the plywood, I finish the drilling on a drill press to ensure the holes were straight.

Sanding the radii presented a challenge. I needed a curved sanding bloc. I found that the backside of the rubber sanding blocks I have would work for this, as did the sticky back sandpaper I have.

I rounded the top corner with with a 1/2” round. Then painted them with a primer (happened to be white) and then used a roller to put on the gloss black enamel latex. This left an interesting texture and in places the white of the primer shows through, which gives them a bit of a marble look.

I used 1/4”x2” threaded knobs for the levelers and put nylon acorn nuts to keep the floors from being scratched. At first I was going to use threaded inserts, then I found I could thread the 3/4” plywood with a 7/32” hole with a 1/4x20 threaded rod with some wax added to the rod. I ran the rod in and out a few times with a drill to work the wax into the wood. It makes for a tight fit and I don’t have to worry about the levelers backing out with any vibrations.
I added sheet of adhesive back black felt to them where the speaker will mount. The thought for this is that the bases won’t stick to the speakers and it will keep the interface from making any noises.

I used black button head screws with Allen wrench sockets, through the base, to attach the base to the speaker and threaded inserts in the bottom of the speakers. The only thing I would have done differently would be to put the inserts into the speaker bottoms long before I put the drivers in...
Done!