What did it fail for
The reasons it failed the inspection were mainly rust problems. All the brake lines need to be replaced, the doors and one rocker panel need to be welded, there are some "wrong" old weldings (done by a previous owner) and there are oil leakages of the engine and transmission (a never ending story).
It lost it historic licence, because the examiner did a reclassification of the car. The classification is done by German school grades. 1 equals "very good", 6 equals "very bad". Your car needs a grade 2 to be registered as a historical vehicle. The examiner gave the car a 4. More or less subjective, but I can't change it.
Looks like you went through a lot of effort and money to save this car!!!
I did. The car has always been very special to me. And as it is one of seven that came to Europe (and one of 1461 V8's build in 79), I just thought it was worth it to bring the car through time. But it has also been a struggle (well, you will know that too). Especially the unstopable leakages have been a pain ... The car needs an engine pull and again some good body work. More than I can do.
And I also had some changes in my "petrol head" being. I discovered electric cars
Quite a change of paradigm, but also loads of fun. You can read our electric adventures here
http://www.arachnon.de/wb/pages/en/welcome.phpmarxx