For this pattern, the rows are more like a guideline; what you really need for this pattern is some measuring tape. I made this as close to the actual measurements of a real gbc as possible (Pillowcase is 6x the size of an actual gbc) so sizing is paramount!
Attaching the gray “screen” part is a bit unorthodox, (which makes it weird to follow) but I couldn’t think of another way to do it. Perhaps if you make the screen separate it would look better. Feel free to experiment!

Please contact me if you have any questions~