Looks cool! Are you planning on leaving the body shape the way it is? I would consider using a template and router to make sure the shape is really perfect.
To your fretboard taper question:
Is the neck already tapered? If so, then you can trace that onto the fretboard by laying the board on top of the neck with the centerlines lined up, and then marking the width of the neck at the nut and the heel. Then you will have points at either end that will show you how it should be tapered. You connect the lines and there you have the shape of your fretboard. Next, you do a rough cut on a bandsaw to those lines. from here you can go two ways. You can either sand it carefully with a sanding block until you get to those lines, or a method i prefer, glue the board onto the neck with centerlines aligned, clamp it really well until the glue dries, and then use a router with a following bit to trim the excess to exactly the shape of the neck.