Your car is absolutely fascinating to me. I am a total nerd when it comes to the history of the Nova and ALL of its varients, and you're car is a total anomaly. Thanks for posting the walk-around video (and other stills.) Those were helpful in trying to figure out what your car represents.
I'm very surprised that the hood area looks like continuous gelcoat as if it were pulled from a mold (rather than an obvious graft.) I have tons of old brochures about the Cimbria and there just simply isn't anything official from the company in that exact configuration. Yes, an individual builder could have make one-off modifications and then made a mold so as to have a clean, thinner, stronger shell (than a first gen Cimbria with tons of Bondo would have provided.) But who does that?? Doing so is expensive and difficult and just... isn't ever done. That's such an odd find.
Here are two pics of my silver Cimbria which is definitely a first generation Cimbria with almost no modifications from factory:
View attachment 9920
View attachment 9921
That's what a Gen I hood, headlights, doors, side scoop, and rear hatch look like.
Your hatch is also the "Mangusta style" Cimbria hatch, but yours has that extra row of louvers in its bottom 1/3. And something about that unique hatch seemed weirdly familiar to me.
20 year ago I used to troll the internet for any and all images of all of these variants I could find. (Today there is lots more out there and pics are more readily available.)
Anyhow, that mild obsession has given me a deep pile of archival photos. And I went through those photos tonight. And I found these:
View attachment 9922
View attachment 9923
It's the EXACT same modifications as your car. In fact, we can't be certain that it ISN't your car. Because it is/was the only example I was aware of and it never showed up in any brochures, I've always had it filed under the "one-offs." And either it IS a one-off (and this is an earlier build of your car) or else someone really did make a mold and produced at least...two(!) I don't know which would be cooler.
At any rate, thanks for posting your find. We look forward to seeing your progress.