I knew I would end up with a finished neck so I cast on and worked the ribbing to start rather pick up the stitches and knit the ribbing later.

Used knitted cast on to cast on the underarm stitches when separating the sleeves from the body. Omitting the purl faux seam stitch.

Changed the hem colorwork a bit by knitting 2 rows of colorwork and then the 2 rows of MC before beginning the ribbing.