You might want to check a parts source like realOEM or MaxBMW. I believe they changed something about the seat mounting on the last few years of the K75. I have a Corbin on my K75S with the side panels that go with the fairing. Mounts the same as the stock seat. I keep tools in the tray over the battery since there isn't much room in the rear with the anti-lock computer. Plus I'd rather have the weight in the center of the bike. Body parts show up on ebay regularly. Good luck.
john