Originally Posted by T-Mar

The Portacatena dropouts were available from the 1978 model year to at least the 1983 model year and possibly 1984. However, the presence of recessed brake bolts limit the oldest date to circa 1981. Guerrciotti has introduced the front derailleur hanger, on the top models, by at least 1983. So, assuming it isn't a tre-tubi or lower frame, it would appear to be circa 1981-982, based on frame characteristics.

Columbus changed their decal style for the 1978 model year, when they introduced KL, Aelle and Zeta. This is the pre-1978 decal. While it's conceivable that Guerciotti had some old stock lying around and/or were not fastidious in rotating stock, the odds of such a decal still being in use as late 1981-1982 seems unlikely. The decal vintage is definitely in contradiction with the frame characteristics.