I love the Harness Top Sewing Pattern above. I don't know how to adjust the size to fit my Standard Poodle, Sherlock Holmes.

The measurements I came up with are: Center Back Length 23.5", Neck Circumference 18", Girth Circumference 29", Center Front Length 21", Chest Width 3"

I don't know how to apply the measurements to the pattern. I really don't sew but I think I'd like to try this to make a new vest for my SD. I've bought two vests at considerable expense but they shift on him due to his narrow chest and significant length. He is a lean, long handsome boy. :)

Can anyone help me?