Vertical stabilizer spar prep and initial riveting

This afternoon I placed my first call to Van's builder support. There were a couple of things I wanted clarification on, although I'd gotten some good results searching the VAF forums. Van's builder support phone line is open 7:30 - 9:30 am and 3:00 - 4:00 pm Pacific. I called at 3:04 and was 8th in line on hold. I'm curious to know whether this delay was due to the long weekend or if it's an ordinary amount of time. Anyway, after waiting 45 minutes on hold I spoke to a representative who answered my questions:

1. RV-12iS page 06-03, figure 3: is the "3/16, 4 places" caption a typo? I only count 2. Answer: yes; it should either read 2, or the other two quantities should be 8.
2. Page 06-04, figure 1: does "flush this side" mean that's the side I cut the countersink into, so that after riveting, the part is flush on that side? Answer: yes. "Flush" refers to the shape of the fastener after riveting. Cut the side indicated by the arrow.
3. Same figure: my countersink cage is too wide to allow countersinking the #40 holes on the VS-1212B that are closest to the flange. Should I cut them by hand? Answer: yes. Practice on a scrap 0.032 sheet first. I had great success just using my powered screwdriver with a 100 degree hole deburring cutter, as it's the same shape as a countersink cutter. Cut slowly and check your depth often with a 426 rivet.

I read online that countersinking such a thin sheet can be difficult, so I fabricated a small wooden jig to place behind the spar. This worked beautifully.

Finally, I encountered a discrepancy when I went to rivet the upper and lower spar caps to the spar, and reviewing the previous day's instructions I found that I had forgotten to match drill the holes on the spar flanges. I fixed that today and riveted the upper spar caps using the wedge tool I fabricated on day 1.