I would just use 3-views. I've been telling folks for years that a decent 3-view with sections is almost a Guillows plan, if you draw in the keels, formers, and stringers. That was one of the best things I got out of building Guillows kits early on. I just finished yet another Guillows keel-and-former method scratchbuild of a Miles Aerovan. It was a pretty straightforward build, and actually a lot easier than the build I'm starting now where I have a "sort of" plan. I say sort of, as it's lacking a lot. Sometimes better to just start your own drawing from a 3-view. Once you put a bit of time into them, you get good and fast at it. I'm about 50/50 when it comes to using a plan, versus just sketching my own with a 3-view. Plans are constraining, and not always accurate either. Usually some rework will be required to suit your requirements, sometimes making it not worth even using. I probably have no more than a few hours invested in drawing time for the Aerovan below, which is about average for these builds.
All good 3-views are a Guillows plan waiting to happen.
Guillows keel and former design.