I'm pretty much ready to start building the frames for my Flying Saucer build. I'm stretching it from 12'3" to 13'6" long. I hit a bit of a snafu on the building form which luckily ended up going my way anyway (many people say raising the height of the building form makes it much more comfortable to work). Instead of having the uprights for the setup members be 15" apart, they were 18" apart and 24" tall. The plans for the flying saucer recommend the setup members are 24" tall at the top and 18" outside to outside. While they are 18" outside to outside, the top surface of the longitudinals is 29.5-29.75" tall (from the floor, not from the bottom form member) since the 2x6 setup member is now blocked on top of the 24" tall verticals rather than alongside it.
I'm having an issue finding what the Set-Up Level for the Flying Saucer is anyway, and I don't know how this change to the form will affect it--will it just move it the height of the 2x6 further up? Same with the blocking for the stem/breasthook--will that be moved approx. 5.5" up as well?
Thanks in advance for your help. Here's a picture of my building form, for reference.

Matt