Each of the concrete blocks is dug into the ground a ways, to ensure a comfortable building height. I was careful when digging each hole to not disturb the bottom dirt too much, and filled each hole bottom with a packed-down sand\gravel mix. The saddles on the pier blocks are the adjustable kind, and this allowed me to get all of the beams pretty close to level using a high-quality bubble-level. (A laser level would have been more accurate, but I'm pretty sure I'm close enough.)
Once levelled, I packed more sand\gravel mix around each pier block, re-checked for level, then removed the beams & saddles and layed down my blue poly tarp for a moisture barrier. I cut a small hole in the tarp over each hole in the pier blocks, and inserted the saddle-posts through the tarp into the blocks. Then I put the beams back on, re-checked for level, and secured them with screws to the saddles.
I now had a pretty stable base on which to mount the main strongback frame, built out of 1"x6" boards as described in the plans. This is what it looked like:
After putting in more screws, rechecking level, mounting the station cross-beams, and adding my center-string, I had this:
One of my neighbors has a custom woodworking business that he runs out of his home, and as it turns out he has a CNC machine in his shop. Isn't that great? Long story short, I obtained the DXF files from Ian and my neighbor used his CNC to cut the float form frames for me. I was very pleased with the results:
Next I anchored each form-frame front-to-back, so that they were vertical:
Next up was ripping a pile of battens...
...and mounting them on the form frames: