The 2001-2004 Bullitt wheels have a +30mm offset and a 5.72" backspace. If you are trying to get to a vintage-friendly 4.5-4.75" backspace, then you want a 1" to 1.25" spacer (adapter, actually). Personally, I think you might find a better fit with the 4.72" backspace that the 1" adapter provides.
The 2005+ Bullitt wheels have a 6.29" backspace (+45mm offset) and need either a 1.25 or 1.5" adapter to fit most vintage cars.
You might have trouble with clearance if you have some aftermarket uppers (GW comes to mind), as these are made with a different shape than stock.
Daniel