After much research on this board, I bought a set of 5000 lb GoJaks on ebay (item # 180189773243 ). Finally opened the box, connected the wheels, and positioned them under the wheels of my son's Boxter. Let's see....an 11 inch wheel doesn't seem to fit on a 9 inch GoJak. Here's the deal...I will sell this set for $50 less than I paid which would be $250.00 plus the cost of shipping. Anyone interested before I put it up on Ebay?? My math (stupidity) error is your gain.