Anyting by Koenig Specials or Sbarro would be in the running here, if not the lead. I love those creations, but they are pretty far up on the outrageous ladder.
Looking for one (in France), I drove the same (but with pack performance). Despite all the videos I saw (including yours which is very interesting), I did not expect that. Coming back home, my wife asked : « what’s the point of having such a powerful car ??? ». In one word: emotion. After just 15mn riding it I was like a kid. Until you have not driven a car of this class, you cannot know what it is even if, like me, you have read and watched hours and hours about them.
The Carlsson SL74 R129 is also an important car. Carlsson stood out from the crowd by fitting a 7.4L 580HP V12 and a six-speed manual gearbox. Unfortunately, they only made 2 or so of the legendary C74. Thank you for the videos, they're awesome, the R129 chassis is awesome, and cheers!