If you get a guide wheel(s) with your rake, it has wheels on both sides (the Guide Wheels /forums/images/graemlins/grin.gif and your Tractor Wheels). Adjusting the length of the toplink will "tilt" the rear guide wheels up or down in relation to the rake tines, allowing you to regulate how much bite you take with the tines. As long as your tractor has position control on the three point hitch, so it stays where you set it, you get the same effect as if you had a MM rake. Since there is no down pressure on the 3-pt, it will raise slightly when your front wheels go over a bump, and the rake will not dig (much) deeper. When your rear wheels go over a bump, the rake tends to take the top off the bump. Clear? /forums/images/graemlins/confused.gif
Recommendation: When you get the rake, make sure the guide wheels do not attach to the ends of the rake, or they will stick out beyond the rake when you angle it to sidecast the material you are raking -- or when you are trying to pull material away from a fence or wall and move it back towards the tractor. On my 6' Leinbach rake, the guide wheels attach about 12-16" in from the ends of the rake, so the wheels follow the rake and do not swing outside the path covered by the rake when it is angled.