I'm with those folks who say build it as if you owned it back in the day - what would you have done? With the Bottecchia brand that I favor, I don't think you could narrow a frame down to a single year in most cases anyway. When I got my Giro d'Italia the only original parts that had a date code were the hubs dated '72 so that's what I call it. Beyond that though, it could be anything from a late 60's to '74 or so which gives you a range of stuff to work with.

I've only been "busted" once for my "incorrectness" - a previous owner had replaced the original derailleur on my Bottecchia with a Suntour Honor. According to the catalog the original was an old style Record (it wasn't but that's a discussion for another thread) but since those are harder to find and more expensive than Nuovo Record I picked up a Nuovo Record RD off eBay. Purely by chance it happened to be a '72 and had a bit of wear and a few scratches so it looked perfect. So one day I rode it to work. One of my coworkers, who rode extensively back in the day but is not a vinatge collector at all, spotted the Nuovo Record derailleur right off. "Somebody must have upgraded this" he noted. "Wouldn't have come with this bike". Oh well. It looks good to me