Jon,  

Don't mean to nose in but have been down that road.

Having the same problem with my 12 row end transport.  Here is a link on another forum discussing this.  I have some tech literature on it that I am going to review and see if I can come up with something other than stops or spending significant $$$.  Let me know if you come up with anything and I will do likewise. 

The 20 inch height is correct.  When you disable the automated stuff they suggest hanging a chain down 20 inches from frame and lowering it to there.  I don't like running like that....is only a last resort.     

 http://dgroups.agriculture.com/n/pfx/forum.aspx?nav=messages&webtag=agmachine&tid=29121