In the olden days (the dark ages), there was rarely a bike that you bought off the floor all complete and ready to go. By hook or by crook you acquired an italian frame of suspect quality/origin and built it up as you could with pieces and parts scoured from near and far
From my recollections, 80's Campy was beyond terrible. Brakes sucked, shifting was no good and freewheels were a no go. I came from the school that every bike had to have 1 Campy part and the rest was practical. My bike, and just about everyone that I knew, had a "salad" group on it ...and quick release paint. 6400 ultegra was damn good for the $, Campy crank/headset/front hub and ultegra shifting/braking. Practical and it worked, fairly common back then
For the OP, put that kit in a box until you find a museum piece to install it on and get a proper kit that works if you're going to actually ride the frame
FWIW: A proper Eroica bike would be a ratty italian frame with square wheels, salad kit, broken rear hub, benotto tape, seat slammed all the way back, 140mm stem, 44cm deep drop bars, 12/18 gearing and a giant "Power Bar" sticker on the top tube. And a matching look of misery on the riders face. The good old days
