Tony,
The frame is just too small for you. I think you would be much more comfortable on a larger frame.
4 inches of clearance over the top tube says it all. An inch is plenty. Your top tube is too short and you are all scrunched up. You don't need to spend $$$ on a fitting as there is plenty of info on the net. Try
www.rivbike.com and look a LeMonde's fitting rec's too. The salesperson that sold you that bike needs to be better trained.
I am 5'8" and ride a 55 Bleriot. I was in between a 55CM an 57CM but chose the 55. The 520 is a touring
bike and the Riv method of fitting applies.
http://www.trekbikes.com/us/en/bikes/2008/road/520/520/