Thanks Wokkaboy. I have plenty of sandpaper left from my previous kit. Also have a dremel 4000 with the normal kit attachments as well as a finishing sander.
Was thinking of using the finishing sander to get an flat "angle". Then sanding using a shaped sanding block or perhaps one of those rounded cutting bits on the dremel. Probably best to practice on a piece of wood first I imagine, don't really trust my (non) woodworking skills, although I'm looking forward to this build as a bit of a challenge.