With almost any block, the easiest way is to draw it out (graph paper can be used as 'real' size - squares are 1/4"), cut it apart and then add your seam allowance. Use these as templates. Sometimes by adding the seam allowance you will come up with a crazy length (16ths or worse). So it is easier to use them as templates or tweak your block to more workable sizes. The first time, I use the paper and lay my ruler over it with the seam allowance added. If I decide I like the block and will use it a bunch, then I glue it on a harder stock or template plastic and cut it out.

Holy moly did you pick quite the project!

Glad you found a solution. For future problems, try paper piecing.

That is a great chart and the variations are really interesting. Thanks for the link.