Mustang only sells one type of seat for the Valkyrie. It fits all models. I talked to Mustang several times about thisand they assured me that their seat fits everything. Of course there are different options that can be added when you buy one like the backrest, studs, etc.
Brad
Absolutely correct... I had a Mustang on my 97 Standard and then moved it to my 99 I/S when I got it.