Then you have to order special proprietary inserts from Kohler (they don't come with the toilet seat). It's part #84999. Two crummy little bolt inserts with some other junk you don't need. Price? FORTY-SEVEN DOLLARS!!! Yep, you cannot put that new toilet seat on without the $47 (...
If there is no shut-off to the water supply right at the toilet, you will need to turn off the nearest valve in the cold water line bringing water to the bathroom where the toilet is installed. Remove all of the water that you can from both the flush tank and from the toilet bowl...