I have had a response on my 504 wheels wanted thread and was asked if I was after the early 504 wheels with nuts like the ones on the 2CV with the attached washers. I am not aware of different ones, anyone knows?
504 wagon wheels do not have washers attached to the nuts and the rims have a taper for the nuts to lock in.
To be polite Ian...I am not sure anything is correct !
My wagon has 12mm nuts.....my sedans have 12mm nuts.......504s run GTI alloys so they are 12mm as well.......but a 604 has 14mm studs so maybe this is where you were coming from.