The rear curtain goes on first, and the bow height has to be right before you staple the rear curtain to the rear bow. There is an opening in the top that gets stapled to the rear bow. If the bow height isn't right, the opening in the top won't line up with the center of the rear bow. There's a piece called wire-on that is stapled over the seam in the top at the rear bow. If the bow height is off by an inch in either direction, there's no way to cover the seam with the wire-on.
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