285s: Stock Wheels + Spacers to new 17x9

It’s time for new tires and I’d like to get rid of my wheel spacers. Help me do math stuff

Currently have stock wheels with 1.25” spacers, 285/75/16 Hankook Dynapro ATMs

Stock wheel: 16x7 +30 offset
1.25” spacer = 31.75mm
Resulting in -1.75 offset (?)

Switching to a 285/70/17, probably KO2’s. Wheels are 17x9 with -12 offset.

The change in offset should push my tire out roughly 0.4” further than my current set up, but since I’m going from a 7” wheel to a 9”, the tire will stick out 2.4” (0.4” + 2”) further than my current set up?

Am I understanding this right?

 

your math looks good, With 285s and your wheels with -12 17x9 you will be around an inch to inch and a half outside your wheel well.