There is a large difference between backspacing and offset. I even used the wrong term in my post. For that, I apologize.
Backspacing is measured from the rear bead lip plane to the center mounting flange.
Offest is measured from the wheel centerline plane to the center mounting flange.
You should get a wheel with zero offset or four inches of backspacing.
What Tom has is standard fare and should be perfect for your application. Unless you want your wheel/tire combo to protrude extremely far outboard and you enjoy replacing wheel bearings, etc.
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