Rob and Phil,
Again many thanks for your advices,
and Im sure that without having them whole thing would be much more difficult to bring it out and I could dare to say impossible.
Now, some dirty work against our enemy: Rust!
Passenger's door before, with some rust at the lower part, and after surgery:
Note the laminated layers of paint
, the very first initially was dark blue, after that was canary yellow, and the last was something between brown and grey..
For that reason I didn't find any stencils or serial numbers at all..