It is likely I will wind up with Mojo blocks and a Mojo bar.. but I am frugal and this was to be an inexpensive project so...Here's what i did today using some scrap stuff.
The brown plastic is leftover vinyl lattice... it is perfect for taking up the play in the rim clamps. I then had to drill the pin holes out as only one side fits after the shim is installed..
Because i am lazy, I did not take the lead screw drivien rim clamp off... I simply forced it into the space using the lead screw and a block.
The clamps are now very stable and stay at 90 degrees.
The white plastic I used for the rim blocks is leftover 1"x4" PVC Trimboard... I think it will hold up... if it doesnt I will by some higher density plastic. (onlinemetals.com has great selection)
The vinyl downspout I melted over the ends of the HFT tire bar with my heat gun, then trimmed where i think it will work then zip tied... we will see...
Now i gotta try and wear that rear tire out faster...