The confusing frame on sale from our friend in Italy has a fork stame of "20" and rear drop out stamp of "20" which suggests to me that the two are a matched set:
He has/had a number of other Colnago vintage framesets on sale and still in the wrapper that look dead-on, bone original, N.O.S. God only knows where this stuff turns up!
I have purchased many items from this seller over the years and he is the real deal, very reliable.
Jeff Pyzyk
Milwaukee, WI