Check with Holmes wrecker company in Chattanooga TN; I also saw another large towing manufacturer there off of I-40, but I don't recall their name. Miller industrial , maybe ? It had a welding company name (by coincidence).
These would be new kits, of course, but you did ask for a lead... Holmes is/was the authority on towing- the International Towing & Recovery Museum is also there in Chattanooga.
Welcome to Stovebolt.
Brad
Edit - it is Miller
Last edited by Uncle Brad; 11/25/2015 9:59 AM. Reason: name verified