On the LH wing the outboard seam did not come out straight. It was bowed in towards the root 3/4" in the middle on the top and bottom. I had followed the directions for shrinking an envelope which said to start at the seams and slowly work away from them to keep them straight. It made sense but only worked on the inboard seam. This time I looked to see if I could figure out why and prevent it. I realized the extra fabric around the nav light was probably the cause. The envelope fit tight at the last rib where the metal tip starts. From there outboard it was very loose. I started at the seams with a quick 250 degree shrink on them and the rib bays each side of the seam just to take out a little slack but not enough to pull the fabric tight. I then went to the tip and worked like a fan shape from the nav light inboard on the top and bottom. I worked this just enough to get rid of the slack and pull the fabric so it touched the edge of the tip with no big wrinkles.
Then I went back to the seams and did a slow shrink all the way along each seam. This was to pull them tight cordwise to help resist spanwise movement. From there I followed the original procedure of shrinking out from the seam doing one bay on each side then flipping to do the other side. Do another set and repeat
With the wing tight the seam is as straight as it was sewn, much better.
The wing is now ready to cut just enough to get the strut fittings to slide through. It looks strange to leave tents around such things while shrinking but it's much easier to get the cuts in the right spot. 
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The cut fabric was glued to the spar and fitting plate. The gas tank filler and sump holes were also cut and the fabric glued down. Once the glue dries its easy to shrink around the spots to remove the slack.
The fabric was the shrunk at 350 degrees and the first coat of polybrush applied. It always looks strange at this point, with visible drips on the inside, but comes out very smooth.We're ready for reinforcing tapes and rib clips but we've lost the sun light and I'm tired.
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