Ah, my favourite subject!
So... if your 1955 is German, hubcaps, bumpers and all handles will be painted body colour or L226 Silver Grey. There seems, from period photos, that both were available.
Headlamp rings were never painted but chromed, unless you had a pre-May 1949 car!
Only one horngrill should exist, the other wing being left plain. That horngrill should be painted like the car if the car is German.
A German Standard will have its front hood handle left in unfinished dull metal (unchromed and unpainted).
Yes, there were some Standards that came factory-fitted with sunroofs if requested at the time.
If your car is an Export Standard, ie. from Belgium, Switzerland or Holland for example, bumpers, hubcaps and all door handles would be chromed.
The front horngrill will also be left in shiny metal finish.
The front hood handle will also be chromed.
Some Standards also had a waistline painted, most of them did from the Oval-era onwards, it would seem from period photos. This waistline was white. The coral red waistline was only for splits.
In both cases, German and Export models, the headlining is reduced to a sparse rectangle, with exposed body-painted metal everywhere else.
German Standards have no carpet in the rear luggage trunk but a folded matt black cardboard panel. Exports mostly had a piece of carpet.
All Standards have the three front carpet panels (brown/beige) and carpet runners over the heat exchangers. A 1955 would have a ribbed rubber piece over the front section of the central tunnel from the handbrake to the pedal area.
For 1955, the colours for Standards were L37 Middle Blue and L225 Jupiter Grey. I'm not sure if L41 Black was still an option.
Some Standards were exceptionally ordered in other colours but these are rare cases.
I'm probably forgetting some things but this should get you started!
For any more info, help will be at hand!
😃