Hi I have a 2013 sportsman 500 and im always towing heavy loads. Recently (last 50 hours) it has been a straight hitch trailer that puts a lot of weight on the rear. The one trailer weighs about 500 the other weighs about 1000 and I often load them with logs the loads vary from an additional 1500-2500+lbs ontop of the trailer. All depends on type of wood size and how dry it is. My sportsman is hurting now the shocks go the whole way down with just me sitting on it and stay down. I have them on the stiffest setting. Will 800 700 600 or older 500 shocks bolt on? What will? what are good springs for it?