Colnago was not the only framebuilder to market Saronni frames, and I'm confident that Mr Anonymous Pawnguy's frame was not made by Colnago or any of his elves. Tecnotrat, better known nowadays as the manufacturer of De Bernardi frames, sold frames with Saronni stickers in the mid-eighties. About 1988 or 1989, they stopped using Saronni decals, and started using the DeBernardi name. Interestingly, the first batch of Tecnotrats imported into New Zealand in 1987 had Ferrarri stickers.
All the Tecnotrats that I've seen had English BB threads, as does Pawnguys frame. Tubing was variously Falck, Columbus Aelle or SL Tretubi, though I think that almost any Columbus tubeset was available to order. I'll try to exhume & scan a Tecnotrat catalog later in the week.
David Benson
Auckland
New Zealand