m@ hasn't posted since last August, I'd try pm'ing him. If he replies, post the info. I may do this mod this summer as well - ever since I cut down me seat on my 800, I've felt a little squooshed. I figure I'll make plywood templates, shape them how I want and then have them cut out. I may have them chromed as well.
There'd be no reason you couldn't contour them more as long as you don't undermine their strength. I think m@ wanted maximum strength and had limited styling options since he was using a dremel to cut them.