Wow! I thought I was going to cry trying to graft the new length onto the cardigan. Then I finally "got it." I had to let go of any previously memorized methods (the old "knit, off, purl, purl off, knit" mantra). I made a swatch with one row of contrasting color and copied that. I've done both fronts, now just the back to go. I can only work on this during naps, so it's going super fast, but I no longer have to puzzle over every stitch.
The brown yarn is the row above the graft.
Ignore the weird color changes, it's just the lighting, and bad photography.