Terence, same thing happened to my driver's side rear fender lip... chipped/scrapped a bit of paint off backing into garage.... dumbo inattention on my part.
If originality's important, don't put on the chrome garnish on the fender(s)... they were somebody's idea of an aftermarket glitz.... MB's weren't produced with them, nor was there an MB option for them on the W113's.
By the way, if a car is entered in a show (MB or classic car show), the fender garnish is an "authenticity" deduction (50% of points), vs the paint scratch/removal a "condition" deduction (25% of points).. so from that viewpoint, whether ever considering having car judged or not, it gives you the perspective of which is more important to MB enthusiasts who value originality. Of course, if you're trying to sell the car, an unsuspecting buyer would love the glitzed up fenders, and hate the paint damage, so you could perhaps get a better price with the glitzed up fenders.
I'm going to have my damage painted/blended when I get around to it... but in the meantime, the MB crowd of enthusiasts I meet have only remark about the damaged paint on the fender in idle passing, if they even see it... other parts of the car's paint, chrome, interior, engine compartment overwhelming the minor paint damage. However, while I say that, thelew's red 250SL is in such beautiful condition in every respect that any paint damage anywhere, especially on the fenders would stand out like a sore thumb.