Today, I decided that I would mark the rib stitches and punch the holes for the thread. I made a mistake marking the rib stitches right off the bat. But, it was easily corrected. The correct way, and the way I did it correctly, is to mark off 1/2 S from the leading edge of the rib for your first mark. S = 2 1/2 inches in the prop wash and 3 1/2 inches outside the prop wash. I marked my changes on the material with a plus sign.
After I marked the correct rib stitch locations by the ruler, I went back and moved the stitch locations where an obstruction would be. I then went back and marked a "O" on all the ribs the had the compression ribs in place.
I then went back and punched out the holes for the thread with the tip of my pencil. On punch was a little larger then I wanted but it worked out fine in the end.
I was surprised how fast that went and decided to start stitching my unobstructed stitches and see how far I could go. I was surprised that I was able to get all my unobstructed ribs done. I remembered that the trailing edge on all but one of the ribs was unobstructed so I stitched those as well.
I was actually able to get a couple ribs on the top with the curved needle for the obstructed ribs as well. My back was hurthing me, so I had to stop.