Let's see how this goes for a start.
Bow Transom
This is the aft face. The edges will get beveled after the building form is completed. You have to figure out the bevels by wrapping a flexible batten over the forms. the batten and thus the planks should lay fair on the bevels.
The notch shown is for the keelson. It should be 1/4" deep. ( I drew it deeper than that so it would show better in the overall view.
See below) The notch is cut after the form is setup.
Form No. 1
This won't get beveled but will get a beveled notch. The notch depth is determined in the same way as the bevel on the transom.
Form No. 2
No bevel. The notch on this one is straighforward. No bevel required in the notch which is 1/4" deep.
Form No. 3
Treated the same as No. 1
Stern Transom
Mounted vertically. It gets a notch similar to the bow transom. Again, the notch is cut after everything is set up.
Form Spacing
Note which face of each form is located at its station.
The forms and stern transom are mounted vertically and must be parallel to each other. The bow transom is 12° from vertical. Be sure to align their centerlines so the boat will be symmetrical. I made the forms out of MDF. Plywood will work or you could build open forms out of inexpensive framing lumber as long as it is straight.
Use scraps to attach the forms to the base board. the dimensions of the base board aren't critical but it needs to be straight and flat. There is no sweep to the sheer on this boat so the the top edge of the top planks (sheer strakes) will fall along the outermost corners of the building frames. Keep in mind that you will need to be able to reach up inside the boat with your hand and with clamps so make the base board narrow enough for that.
There are knees that join the bow and stern transoms to the keelson. I haven't drawn them yet but they are made extra long. The transoms are attached to the base board through the waste portion of the knees and some other blocking so there will be no screw holes to fill later.
The next installment will come sooner or later.