I'm in the process of doing so, but if you want to keep it C&V in mentality, you kind of have to work with what they had available in the 80's.
Base of the build is an '89 Centurion Ironman frame, geometry is the best I can find, 2cm shorter than I usually ride, to make the aero's fit better.
Seat post will be the minimum set-back or none, try to get me forward a bit. A little higher than normal and tip the saddle a bit nose-down.
I'll cut off the bars just below the brake lever clamp, so I can use the std brake levers or brifters. Keep the stem down a bit to keep the forward-tendency.
Scott old-school aero bars on that. If they're too narrow, I'll simply cut them in half and mount 'em wider.
Skip the FD and small chain ring, terrain here is not hilly. 12-24 rear will do. If I go 7-sp, use R DT shifter only. If I go 8-sp, R brifter only.
That's the start. Things will change, I'm sure.