Ah the shutter plank. So the shutter is supposed to be one of the hardest planks to fit, there is no wild edge. Its got to fit first try.
I don't think its the hardest thing going, it does take a lot of exacting documentation. So in the above photo i tried something completely different, scribe both sides. This does take some time two or three times longer than the double tab method, but it sure does make one hell of a accurate pattern.
Once all is into shape into the steamer and then pound and clamp into place.
Perfect fit first time. Woot!!