Welcome to the forum.
Using the router bit I suggested does not require a tapered board. The bit profiles the board face like in your original post. Cutting this profile can also be done using a craftsman/corob molding tool (if you have one) using this cutter knife set... #31 Corob Taper Edge Molding Knife — Corob Cutters . To make the roof tile on a table saw, you can make angle profile, but only individual angle cuts (one row to a each board.Thanks for the responses. Love this forum!
Yes I have a table saw and did consider that as an option. Now that I can see the profile more clearly in the drawing for the router bit I can see how it could be done. I guess I'd need to use a taper jig to make the cuts as they're on an angle. Then use a round over bit (the ones without a bearing).