I bought the chrome trim from Walloth & Nesh. The window trim is listed here (
http://www.wallothnesch.com/karosseriea ... 51-02.html) along side a tool that may be used to insert/fit the trim into the rubber window seals.
I paid about 70 Euros and some postage for the three pieces of trim needed to do the front and rear screens - one for the front screen and two parts for the rear screen (upper and lower chrome strip). I don't think it's necessary to use the featured trim tool, as with some care you can do the job with a dinner knife or screwdriver.
1. On a hot day park the car in direct sunlight to warm the window seals. Also put the new chrome trim pieces in the car and they will warm up to. Now that the window seals and trim are warm and more pliable.
2. Remove the chrome trim joint covers (one in the middle/bottom of the front screen and one in each bottom corner of the rear screen).
3. Remove the chrome effect plastic trim from the front and rear screens.
4. Clean the rubber window seals (where the trim was sitting). There will be some accumulation of dirt (I used a blunt dinner knife to run around the seal lips and remove the dirt). Do not use a sharp knife as you may cut/damage the rubber window seal (or worse still injure yourself).
5. I then sprayed the window seals with silicone spray/polish to clean/restore and lubricate the lips of the rubber window seals and gave the rubber seals a final clean.
6. I then sprayed the new plastic chrome window trim with silicone polish on the underside to lubricate it whilst inserting.
7. Begin feeding the chrome strip into the screen rubbers and using the knife lever/press the strip into the lips. I found that placing one side in and then levering the other side in (hard to describe - but I'm sure you get the idea) worked best for me.
8. Refit the chrome joint covers (three in total).
9. Give a final wipe/polish, stand back three paces and admire the improved appearance of your e21!