: I was hoping to avoid scarfing on my Guillemot Exp.

While I appreciate the desire to avoid scarfing, don't be in a big hurry to get 20 foot boards at such a high cost. Get 10 and 12 foot boards, which should be much more reasonable. If you can find some that are not clear, but have small knots, you'll save even more.

Scarf 1 or 2 of the 12 foot boards before you rip your sull length strips from them. To do this, rip the boards in half, overlap the top ends by 2 feet and make a single diagonal cut through this overlap, cutting both boards at once.
You don't need any jigs, but a clamp or two might help. You can free-hand this cut with a circular saw, or even a handsaw. (Cedar cuts easily with handtools). Since the parts are cut at the same time, even if you have a ragged cut they will fit together like pieces on a jigsaw puzzle.

You'll have a fast scarf that fits perfectly and merely needs some glue or epoxy. When the glue is hard you rip your strips from these longer planks. As you do your scarfed areas will appear at different spots along the strips. Because of the 2 foot overlap your 12 foot 1x8 will give you a 22 foot long board that is roughly a 1x4.

Ripping strips from these long, narrow boards you automatically get neat, clean areas around the scarfs. No additonal sanding. No color staining around the joint from soaked-in epoxy or glue.

Since you are joining the tops of both halves after ripping the 1x8, your wood should be pretty close color and grain match at the scarfs, making them less noticeable.

Try it; it is fast and simple, and you can use less-expensive, shorter, pieces of wood. A single 1x8 should give you more than enough full-length strips to start with, but you might as well scarf two of the 1x8's and have a few extra long strips to play with.

PGJ