Okay...when you say SSK on the right side and K2tog on the left...does that mean no matter if it's RS or WS? I just would start with SSK when knitting across the row, and do K2tog when I get to the other side?
Also, will knitting two stitches to the right and left of each decrease mess up the K5, P1 ribbing pattern? This is more complicated than I thought!
Thanks so much to everyone for your help!