Yeaaaaaah not so sure about that now. It's taken half the afternoon just to get the new zipper in place, and that's without replicating the second lines of machine stitching on both sides.
Oh well, at least I'm getting it done. It's the Pan-Pacific Defence Corps bag I made last year. Nothing I made failed - the zipper itself failed, with the teeth separating off from the fabric. (Goddammit.) It'll be nice to have it back.