The levelling kit is a great idea that is not properly executed. The mounting holes are drilled for 3/8" bolts, but the holes are drilled so close together that it is almost impossible to tighten the nuts because they are jammed together. Also, there is not enough space for a 3/8" bolt head to fit between the mount and the sliding leg without scraping the paint off. You need to drill the holes about 1-1/4" apart, and put a bend in the mounting plate so it is offset further from the leg.
Otherwise this is a great product.