Just got my new MP3 500 stock seat back from local guy Dave Spinazola who's been an auto top/auto upholsterer since 1973. Dave cut the foam back about an inch, (so now I sit further back in the seat), and he shaped the driver's area so I sit IN the seat instead of feeling like sliding off towards the fairing. WOW, makes a HUGE difference.
Dave's shop is on route 109 in Brookfield, NH.....between Wolfeboro & Wakefield on the map, a few miles from route 16. Dave was easy to work with & I thought his price very reasonable @ $75. His phone # (603) 522-6013.
I know alotta owners aren't tickled with their stock seats, and finding an auto upholsterer isn't that easy. If you're near NH this guy's wonderful!