I'd use a bandsaw with a thin blade to do the cut and make DAMN SURE of your cut before you cut out the comb. Don't use a lot of pressure when making the cut or it WILL go "crooked". Then you'll have the fairly complicated job of inletting for it. Take your time and keep trial fitting as you go. Once you get done you'll wonder what all the fuss was about in regards to it being hard to do.
Sometimes you earthlings REALLY amaze me!