what are the stock wheel width(s) on your 5.0?
How close to flush is it? use a level and measure it.
Between the offset and widths, you should be able to figure out at what point the new wheel is flush. Assume 1/2" or 12mm rim flange thickness for each side of the wheel (ie an 8" rim will measure about 9" outside width)
also, the official BCD for 5th gen is 5 on 120mm (not 4.75) and uses M14 studs/lugs.
keep in mind, that you may have to cut the studs down some if the thickness of the bolt on spacer is not very thick. you need to ensure the vehicle stud does not stick out past the plane of the spacer.
http://www.tirerack.com/wheels/tech/...jsp?techid=101