If you are doing the install yourself just set the hitch at it's highest position to pick up the trailer. You can adjust it down easily if you need to.
After you have your 5er loaded for a trip go down and get it weighed. Get a weight on each 5er axle by splitting the axles between the scale plates. If you are within 100lbs between the front and rear axle, OF THE 5er, then you are close enough to the right height for the hitch. Side to side weights are not as easy to get but can be done also, although they have no bearing on hitch height.
If you are over 100lbs difference in weight on the front axle then you can raise the hitch and visa versa if the weight is to heavy on the rear axle. A inch of two of nose up or nose down will not matter except to the axle weights.
