SteppIR uses this method. Maybe they'd sell one of their U-bolt assemblies.
What you suggest works and I have used that procedure, but it only works
if the thread on the U bolt is long enough to capture the eye of the
turnbuckle. Most as found U bolts that I have do not have excess
You don't even need any kind of plate. Just mount the eye of the
turnbuckle on the end of the U-bolt and use a big washer to capture it
nut and you're good to go!
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