I came across this ~1990 Basso recently...everything looks showroom!
Frameset is Columbus 'Tretubi', which is apparently an SL main triangle with builder's choice tubing for stays and forks (whatever they are, these are beefy and one is chromed). Forks are B-logoed, full chrome, sloping crown. There is some damage to steerer threading, but I serviced the headset and it appears to thread/adjust/secure normally.
Came with a complete Campy Athena Synchro 7spd (freewheel) gruppo, MA40 rims & Regina 13-21 freewheel, Cinelli 64 bars/1E stem.
PM if interested in anything...