I need to replace the bugscreen for my son. I was thinking about just putting in the zip system instead but with new screen and some mods. What's the lvl required here when it comes to sewing. I have enough skills to feel confident in simple projects but this seems like it could be a little work. Am I seeing this right or is it simple straight forward cut and stitch. I was just going to make a duplicate of the existing screen after it's out and allow a zipper tolerance and inject thread? Any experience pretty please with a MacCat on top?