I just bought a model 100 plow and have a few questions.  First, where can I find manuals on it?  I have not been able to locate anything in my searches.  Second, how fast can I pull it down the road?  The guy I got it from only lives a few miles away so I drove the tractor down and tried before I bought.  When I got it out on the road, if I went any faster then idle in fifth gear (John Deere B top speed in 5th is 8mph) the plow would sway really bad and I would have to stop and restart.  I had no idea that it wouldn't pull otherwise I would have trailered it home.  It has good wheels and it has been well taken care of.  Is this normal?  I need to be able to pull it down the road as I do quite a bit of traveling between fields and shows.  Is there anyway or anything that I can do to make it pull better?  Thank you
Andy