I modified the seat on the 3R today, having done this previously to a solo Corbin on the Roadster to lower it. In my opinion the seat on the R is too cush (not good for distance). It also cuts into the back of my legs and is too tall (hey, I'm vertically challenged).
It's pretty simply to access the foam- two metal brackets and then staples holding down the cover.
Once there take the bulk off with a serrated knife and then use a wood rasp to shape and smooth. After the initial shaving I'll ride a few times to determine if I want to continue to take off more.
Once done just stretch the vinyl and reattach, or get it covered with something nicer. (Btw, the crack at the nose was already there, a gift from the factory, apparently.)