Cant say much about the frame as im not in to colnago's but The groupset is deffo Campagnolo Athena first generation. The frame would be compatible with that age as well. I'd say at a guess that this about 1991 or 1992. I think the straight forks were popular on Colnago's around 90 - 92.....everyone can feel free to correct me if i'm wrong and i know you will
P.s Saddle looks like a flite titanium....and it looks like a fantastic bike. My friend had one of these with full C-Record groupset and he sold it.....