Actually, that may be correct. I've never heard of the model, but I've heard of NSU and of course, Fiat, but never the two together.
However, a quick search showed that it does, indeed, exist and was built in the correct time frame. I couldn't find any clear pictures of the taillight, but the ones I did find look similar.
Also, check out the Fiat 1100 sedan of the same year, or years. It could be the same part, and I'm sure there's a lot more of them.
Shouldn't be too hard to find. [
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