I have done the exact same thing on my BMW... It served two purposes... converted to 5-stud and also created the offset I needed for my wheels and new disc rotors... If it's a direct slip over sleeve, I would make it a slight interference fit...
Mine was a snug fit, in that I had to gently tap it into position and seat it... I had mine made from Chromemoly though as I have a slight overhang due to the new bearings being slightly winder then the std ones, better to be safe then sorry...