Great bike (wrong headset, btw, and you should take care of that)...

Late 80s early 90s, internal cable routing. Either Columbus SLX or Columbus Zeta (with an outside possibility of being TSX, but unlikely...) If I were to guess, I'd say Zeta before SLX (just from the thickness of the ST and DT). Spreadout stays, this bad boy can take every modern component set you might want to throw its way. It's a repaint, but you probably knew that, and it is well done.

Sweet frameset (get an appropriate headset) and enjoy it!