Hi Marc!
Are you forming the rabbet before gluing on the keel? Probably easier to make the varying angle of the rabbet if done before gluing to the plywood back piece. With only the knee of the head and no actual stem on the kit model, cutting the rabbet at the bow is going to be interesting

Assuming the plans show the line of the rabbet where the stem would be, instead of tracing the line, can you scan the image in the kit? If you can, then you can print it in label paper then stick it on the wood and have a perfect curved line on the stem to cut the rabbet with a scalpel and chisels. You would need a mirror image as well for the opposite side, but easily doable. Just a thought.
Allan
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