I am making a 10ton equipment flat deck w/ beaver tail trailer. It has 2 10K axles. The deck is 18' and the tail is about 4'. The main frame is the frame off a Peterbuilt semi. The cross members are 4" channel. My question is what kind of bracing do I need between the main frame rails? Can I get away with some more 4" channel ran in the middle? I will try and get pics up tomorrow.