Out of an '86 K3500. The new owner bought a dually 14FF to replace the D70 and I asked him about it. He said he needed to call the yard he got the 14FF from to see what they wanted for it. Guy was not at the yard at that moment. What would be a good or fair price to pay for it? It's the longer axle and has only 50K miles on it. It was very clean and absolutely no rust anywhere on it.