Following the SKOSH chart - your experiences?

This was pretty aggressive. Probably more than I needed right then

I was changing from:
Tires: 245/50/15
Rims 15x8
Backspace: 4 1/2”

To:
Tires: 245/50/15
Rims 15x9
Backspace: 4 1/8”

But planning to put 18x9 rims with 275/35/18 tires or something a little wider