I have this nightmare where I remove the carbon (bonded to its aluminum rim substrate) RS81 wheels from my '89 OS Paramount (to put on a new high end road frame that I don't own yet) and it goes back to being just an "alright" bike instead of the second coming of my '88 64cm Davidson Impulse that it is right now.
I have a dream where I take the geometry specs of my '82 Trek 720 and have John Slawta (Land Shark) build me the equivalent frame and fork in carbon fiber. Don't worry, it will still be rim brake.
The real nightmare is selling my big vintage Treks. I've sadly sold many a beauty, even for decent reasons, and I'd like to stop that!