The offsets are not the issue, the offset is the same between 7's and 5's.
The difference is the hub size, the e39 has larger hubs.
You can get adapters made or bore out the center of the wheels to make them fit.
www.enthusiastauto.caContact if you are looking for a car
--2000 BMW ///M5 .:Jet Black on Black:. Individual - Style 65 Wheels; 9.5" Square Set up;275 Tires;10mm/3mm Spacers; Black Kidneys;Muffler Delete; 3.5" Dual Tips; Beast Power Sway Brackets; "Dinan" Ducts; E60 SSK; BC Coils
--2000 BMW ///M5 .:Avus Blue on Grey/Black:. '01 Exterior Upgrades; E60 SSK