I've only been an E28 owner for just under 2 years. When I bought my car the former owner had on the trunk the M5 badge. I immediately removed the "5" and left just the "M". I've noticed that there seems to be issues with this and wanted to follow proper etiquette here. Seems like a lot of people out here in the S.F. Bay Area add the "M" in front of their badge numbers. The E28's that I've seen has it like me just the "M" only on the trunk, so I assumed that would be okay. Just curious how some of you long time Bimmer owners felt about this.