I wouldn't worry about the pitman arm. Your AD pitman arm might be able to be altered to fit the box and work. The spline pattern in most all Chevrolet trucks an cars has been the same for many years.
I'd like to see the unit mocked up by someone. This could be a really big deal!

"Truckin' Around .......... Since 1937!"
My name is Joe and I am addicted to Classic Country Music. I just can't hep myself.
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