So for 3 years I have been trying to get my 04 king to handle like my 04 mountain cat. They are identical as far as rails, track length and track. The king just always had more ski pressure then I liked and I could never get ride of it. The Mountain cat just had a much lighter feel on the front end. So After looking at them both the other day I discover that the rear arms in the rear suspension are NOT the same. The lower Arm is longer on the king. So i look it up, sure enough, the 04 and 05 king run a different arm then the 04 mountain cat and 06 king. The 04 mountain cat and 06 king (as well as MANY other sleds) use this shorter arm. It is a good 1.5 inches shorter. Sure enough after changing it she handles like a dream !! Sorry for the poor explanation. It is the lowest arm that hooks to the rails in the very back of the skid.