Help please! How do I get the thermostat back in?

[Crasher]

Well K stands for Kolben, piston…. It was a pragmatic solution at the time for VW to introduce an affordable water cooled car in the C segment class and in 1969 they hadn’t yet given up on the Ro80. I like oddball stuff like that hence why I have a 1302LS automatic. The problems dealers had weren't confined to the R080 at that time, their electronic injection air cooled models were causing them hell because mechanics didn’t understand them and diagnostics didn’t work very well then, in my early days I used to find that the engine temperature sensor was the main culprit, funnily enough it still is but we have diagnostics to help spot that now.

[FrenchAudi]

The K70 was initially an NSU project to produce something with a conventional engine which would sell and maybe help them out of their financial woes.
I always understood that VW rebadged it and produced it and the Ro80 just to keep the Neckarsulm factory going short term, but eventually ditched them both because of overlaps with other brand cars they produced, and the NSU brand was too damaged to recover. Unfortunately, in the USA, the initials stand for non specific urethritis, which didn't help them much over there.
The last two Ro80's I had were both 1973, but built on different platforms, I guessed this was because they somehow grafted the NSU body onto an Audi platform, as Audi cars were also being produced in Neckarsulm.