Proof of concept from garage stuff: .. that's a 3/4" freeze plug.
Shot from the hip fabbing everything so the angles, clamps, etc need some fine tuning.
Goal was a cheap, universal, bolt-on brace that could be moved between bikes.
Didn't want to start welding on stuff till it proved out.
First wiggle test showed that all of the movement was now below the fork tubes.
Test ride was a big fat yahoo! Road with my hands off the bars....
Front end tracked straight, wander and wiggle free:
Cost for freeze plug: $2.99. Time to build and test: 3 hrs.
PS: The cover wouldn't stay on the seat, even with pro contact spray. Applied carpet tape around the metal edge and then pushed this door edge moulding over the seat cover... holding great so far.