A couple of my centre caps are a bit tarnished and the metal coating around the outside has worn back to the plastic - you can just about make it out in the photo:

Founds a set on ebay for about £12, but just wondered if they are easy to replace, without taking the wheels off? :?
Also, one wheel in particular tends to have a lot of dirt (grease/oil...?) coming through from behind the centre cap when the car is driven on a long run. I'm wondering whether this is a sign of a wheel-bearing issue? I had a wheel bearing go on my E85 so know what that sounds like, but there's no strange noises at the moment.
Any thoughts...?

Founds a set on ebay for about £12, but just wondered if they are easy to replace, without taking the wheels off? :?
Also, one wheel in particular tends to have a lot of dirt (grease/oil...?) coming through from behind the centre cap when the car is driven on a long run. I'm wondering whether this is a sign of a wheel-bearing issue? I had a wheel bearing go on my E85 so know what that sounds like, but there's no strange noises at the moment.
Any thoughts...?
My personal SWMBO has long since given up. I reckon I'm one Alpina bill away from a divorce!