It looks like a "Montello".
The Treviso was a SL columbus tube frame...it's a mid-line model, below the Montello. These were popular racing frames in the 1980's because of their relatively low cost.
If your tubing decal says SLX, you have a Montello, although my Montello and all I can recall have a fully chromed rear triangle. Montello was top of the line. Depending upon size, it may have been an SLX/TSX tube mix.
Your fork crown looks identical to my Montello. Your head lugs look like both of mine, also. Your brake bridge more closely looks like my Montello.
Let your tubing decal tell the tale.
My 1985 olympic clone Treviso was from Denver Spoke and it was metallic blue and IIRC had a painted fork and chrome drop-outs and right chain stay. The first red Treviso was a 1986 model year. One had a chromed fork and the other had a painted fork.
Someone correct me if I am mistaken, but I 'think Gita imported them for awhile.