I assembled the section between the firewall to F6 (seatback) and then started on assembling the fuselage. I didn't pay close attention to the height of the seat back. I had assembled it by placing it on the plans. But the builder needs to keep in mind that there are many areas of adjustment before proceeding. My seat back height was too high, but I didn't realize it. I proceeded to set up my 2x4 on my work bench by locating the F10 bulkhead position and then leveling the top of F10 to the top of F6. Thinking I had things where they ought to be, I notched F10 for the 3/4" stringer angle. I did the port side 1st. But when I got to the starboard side I could see that I was going to cut into the large hole that F10 has for which the elevator control passes through. Since I bought my bulkheads from Peter Beck, I called him to discuss this hole location. He immediately recognized that I had an issue with my set up. After some discussion and measuring, we determined that I had not set my F6 top to 6" above the forward longerons.
So what I had to do is lower the seatback top and reposition my 2x4 so I could relevel my F10 top with the lowered height of F6 top. Now everything was where it needed to be. In the photos below you can see I simply repaired the 1st notch I had cut on the port side of F10 and continued with my building.
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