I'm with Grand Bois - keep the cottered crank and learn to service it. Once the bearing are smooth, clean, and slippery, it will spin nearly as well as a perfect restored Campy Record (well, those ARE awfully nice ... ). The message of that bike is not "look how modern I can get" but "look how great I was in my day, and how well I can perform today, even with my old heavier gear - and my steel crank might rust but it will never fatigue and fail catastrophically!" And if that old Italian style was good for classic powerful racers in the '50s and '60s, are we really stronger today than say, Coppi and young Eddie Merkcx?

If you want a light, hot classic bike that has less history, get a Nishiki, Univega, or Centurion frame and lighten it up, for a really fine go-fast bike. If you're a good rider, you can really surprise some carbonistas on a bike like that.