HC is that your picture:
I am interested in where you got the four clamps that go around the tubes on the left half of the rear dropout. They look like they are stainless straps that form a clamp but are not adjustable. They have black rubber insets that go between the metal part of the clamp and the tubes.
I expect I'll have to experiment to see if the size diameter and shape (round/ovalness) if there is a problem using them on a different application than chain tensioner for the amount of stress they can handle and also the bike tube I have tube differences.
I got some parts that clamp for plumbing of two types, but think I have seen this kind in the picture you posted and may try them instead as they are lighter than the cast metal ones I got. If so I may try to return to Lowes some parts and see if they have the ones that look good for the bike that are one in the picture you took of that plate mount with chain tensioner.
I am making a way to attach a skeleton cover that a fabric will go over to make an art bike vehicle to resemble a California Sheepshead Fish and this will be a way to attach the skeleton and make it removable as well.