I made my own, Can you Fab?? Check out the pics. The large cross brace at rear of frame that holds the upper trailing arms is 3 sided, it can flex.
Between the upper trailing arm mount and frame, Fab up a plate that will box it in.
Tie the lower trailing arm frame mount to the rear frame "cross brace" I used 1 1/2 inch tube. The lower bolts to the lower trailing arm mount with the suspension bolt,{may have to get a longer one} I used all grade 8 ,,, 1/2" bolts, had to ream out all holes slightly. The upper and lower parts of the tube I bolted in place first for proper alignment then welded, I also tide the tube to the factory stamped bracing, removed the upper bolt and welded "plate" on all 4 edges. No technical proof that it helped but looking at the aftermarket stuff available it is similar with the addition of the "box in plate" Sooooo in my opinion it works well
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