I doubt it being Columbus besides the weight thing for the sole reason not having a Columbus sticker. Italian framebuilders would put the sticker on the tubes when they used Columbus tubes. As you got the bike new and it never had the sticker it is highly unlikely that it was build with Columbus. Don't forget the sticker was a sales argument at the day much like the Made in Italy sticker. The Garlattis I have seen were all very nice frames with chromed lugs but never Columbus tubing. So my gues would be Falck or similiar.