Like I said, I've put 20K miles on mine using the supplied plate (not the adapter plate that is extra) and have not had any problems with it. You'll have to drill some holes to match the bolt pattern of the hard mounts. I did this by putting in the bolts then laying a piece of paper on top, marking the centerline of each and using it for a drill pattern. A couple of mine ended up being right on the edge of a sloped area (you'll see what I mean) but, still bolt up fine and have held up well. Be sure to put the plate/top case toward the rear enough that you have clearance with the backrest on the case when opening the seat.Does a person need the additional adaptor plate for $75.00?
Need? No, but it sure makes things easier. If you don't buy it you will have to make your own. I have the additional adaptor plate on my bike. It was worth the extra money IMHO. I also have the liner for my box. Adds a nice touch.Does a person need the additional adaptor plate for $75.00?