I bought the frame and forks from colnagokid, and most of the Shimano 600 pieces from taylorsummers on these very forums.
I spent a long and frustrating day a couple of months ago putting it all together, and trying on various mudguards, and struggling with derailleurs and STis that I really wanted to work but just wouldn't in the end. I also tried gamely to get used to Shimano 600 aero pedals, but in the end I just couldn't do it, and have temporarily gone back to SPDs. It has been through these incarnations:
But now I think I have finally got it just about where I want it to be:
The frame & forks are Reynolds 531cs, the front & rear mechs, shifters, calipers and levers all Shimano 600 Tricolor, Dura Ace 12-21t cassette, original fluted seatpost, GB Biba stem and Tange Allez headset
Silver bars of some kind, SPD SL pedals and I might just be done.
Finally had a ride today that actually does it justice, as I brought it back to my parents' house with me for Christmas and took it round some of West Cheshire's finest roads. The cassette is probably better suited to Holland, but just about sufficed, everything else felt great.