I can't thank you guys enough for your replies! You've been a great help.
The cast on is 120, not 126 as I thought and it is divisible by 4. Instead of 90 I cast on 88 which is also divisible by 4. I'm going to see what happens now when I make my turns.
Gramma if you're starting on this one anytime soon the word is to start with less stitches as and a smaller needle since so many of the comments have been that the end product is gi-normous. I'm also keeping my ribbing rather tighter than usual since I'd like it to be snug.
Okay, going to try this now and see where I end up on every turn and how I'll approach it.