235/60/15 on front of duster?
AJ misspoke (or mistyped) tho he is correct. A seven inch alloy wheel is overall eight inches wide, but a zero offset 7" wheel would have a four inch backspace. A steel 7" is probably around 7 1/2 inches wide.
I don't bother trying to remember which direction plus or minus offset is, since it can't be measured,(you have to know the wheel width) it has to be calculated, unlike backspace, which CAN be measured.