Did a search, couldn't find anything about towing with an ORD schackle flip. I tow heavy trailers often. Is this a problem? Also the ORD web page states that the shackle flip is for trucks with 42 1/2" spring pad centers, except 1 tons. My 1970 K-20 has 40 1/2" spring pad centers. Is this a problem? I'm looking at kit GU28010.