Bill, I think your idea would work fine. This one I cut the slit down about 6″ below the original and then laid the zipper face down on the front of the shirt and ran a row of stitches close to the zipper teeth and then rolled the zipper over and stitched a second line a little father away from the zipper, Zippers are always a little tricky and spend some time thinking them thru as I have gotten one half on backwards before I realized it and had to rip all those stitches out.