Proper offset?

[Spaz]

Not a wiz kid with offset, but as you know i have 17x7 supersleggas, and they are ET37 and i believe stock is ET 30 on a 6.5 so i'm thinking i need about 12mm spacers to bring it back to stock?

And then i think i'd have to roll my fenders >.<

Any advice or opinons would be helpful. Also if you have any suggestions on where i should go about to get some links would be great :)

thanks
-cam

:edited, 12mm spacers:

[rwh11385]

yes, et25 is perfect for 7" wheels.

why would you need to roll your fenders?