seat rail refinishing

[Mark A]

Hi All,
I've had a search on this but not found anything yet.

Any advice on how to refinish the seat rails on my 73T ? What did the factory do, are they galvanised or more likely bright zinc plated? Do I have to separate the rails to have this done? Also i can see there is a plastic bush or stop in there too, is that removable?

Minor issue but they look pretty ropey at the moment with a little surface rust in places, any advice welcome.

Thanks
Mark