Asim Sb.,
I think eventually, in time, your fintail will look no different from the picture above.
Doing a resto in Pakistan helps us in some ways and hurts us in others. Our best ally is the comparatively cheap labour cost. If you were doing this same resto in the UK, the most expensive part of the job would be panel beating/engine swap. On the other hand sourcing out bumpers and trim would be a easy
So for us in Pakistan bodywork is the most doable part of any project. Getting trim and parts is the biggest pain. Your project almost falls prey to the same syndrome but from what I have seen so far, you are way ahead for others in the area of body trim. Front/rear lights chrome surrounds screen frame, side chrome flashes etc. are super. You have already sorted out the roof lining in the most satisfactory manner and by now should be fitting in the dash top.
If I were doing this project back in Saudi, I would be going to Juffali (MB agent in Saudi) for getting bits and bobs. If they didn't have it, they have a service whereby a small deposit is taken from the customer and the item is special ordered from Germany. Can Shahnawaz not be of help here? The good thing about MB's is that no mater what year, parts can be eventually found.
I have come across a very interesting solution to chrome plating by a guy in Germany. Due to the ever increasing environmental restriction and the nasty chemical involved in the chroming process, most chroming places have gone out of business. There is a video on youtube of him using the same stuff they use on glass to make it reflective (mirroring). I'll send you the vid via e-mail (vid has been compressed so it is a bit jerky but you will get the idea). The beauty of this system is that no mater how bad, pitted, bent the item is, it will come out looking stunning. This is because filler/sanding can be used to sort out the item, then spray on base coat and then just spray on the mirroring stuff. Finally a coat of clear lacquer. The disadvantage is that it is not suited to large items like bumpers. Don't know why but apparently it isn't.