Having seen Petep's car at a show, I was impressed with just how clean the rear of the coupe looks once the wiper has been removed, in fact after that show (Tunbridge Wells) it joined my long list of jobs.
Its very easy to do, I think it was around 20 mins, then 10 mins to clean rear screen and apply Rain-X

I much prefer the look of the rear end now and will post photos tomorrow, once the rear wiper is removed, you realise how "Heath Robinson" it looks.

I will post a photo tomorrow