EZ pullover (need help calculating it)

Iam going to knit the pull over from the EZ book Knitting Around. I want to do a smaller size for my neices approx size 6-8. Would someone mind helping me calculate the pattern. I have my swatch and I know the general number I need to cast on for the body.
Just need help calculating the arms and decreasing the yoke and neck area.

Okay here’s where Iam at: :thinking:
I need a body that is approx 29" at its widest point.
My swatch is 6rows and 4.5sts to the inch.
Basic Pattern
CO 119 sts
Rib 2"
Next round inc 13 sts
total of 132sts
knit straight for approx 48 rows (8" approx for length - not including ribbing)
CO 32sts
Work 2"rib
knit straight for approx 48rows (8"-doesn’t hurt if they are a little longer-they grow fast)
join sleeves and body on circular.
K24rows or half the yoke depth (which according to the book is 1/2 the body width)
the do first dec of k2,k2tog around.
work another 12 rows
2nd dec round k1,k2tog around
work another 12
2rd dec around k1, k2tog around.
do ribbing for neck opening.
Hope this makes sense.
:thinking: :rollseyes: