Sorry I thought E55 AMG was talking about the INVERTED CUP body section welded to the inner wings/chassis legs which rests on top of the springs and bears the weight of the car. I think the owners in the USA refer to these body/chassis parts as Spring Perches?? Hence the talk of mastic which masks the corroded welds? Quite common nasty problem leading to suspension collapse!!!! The diagram isn't very clear I know. Lots of postings on the Mercedes shop forum about this. I will try for a better picture tomorrow.