More research into this frame shows that these were manufactured in Italy by ALAN, and badged in the USA by Ten Speed Drive Imports (TSDI); see above photo with partial TSDI decal on bottom of seat tube. These were badged, fit with components, and marketed by TSDI from at least 1985 to 1987 per TSDI catalogues for their Guerciotti line up; up to at least 1988 for the Tommaso badged model. In 1985 it was listed as the "GA 6100-Sprint"; in 1987 the "GA-Aluminum Sprint 105" (the new 1987 Shimano 105 group was substituted for the Campy Victory/Triomphe group); "GA" standing for "Guerciotti Aluminum". They also put the Tommaso name on the same frame (1988 Tommaso TSDI catalog shows this as the "TA 5000 Record Sprint Aluminum" with various component groups available for the finished bike; "TA" standing for "Tommaso Aluminum" . All were from the mid to late '80s and essentially had the same component group/group mix with some differences in actual components: Campy Victory (primary)/Triomphe mix; Campy Triomphe (primary)/Victory mix; Campy Victory/Triomphe/OFMEGA mix, Shimano 105 group. Guerciotti/Tommaso frames are stamped on upper seat tube, after the tubes were anodized, with the date code (month and year of frame completion by TSDI, not date of actual frame, but assume the frame to have been made within a year or less) and frame designation (Corsa, Tourist; believe this has to due with component group/mix differences and marketing). All frames have the seat tube/top tube sizes stamped onto BB shell bottom. I now have 3 of these identical ALAN frames: Guerciotti "SPRINT" (red anodized tubes, stamped "CORSA187",  completed bike built Jan. 1987), Guerciotti (red anodized tubes, stamped "TOURIST486", completed bike built April 1986), and Tommaso (black anodized tubes, stamped "1286", completed bike built Dec. 1986). These are solid frames and ride comfortably for an alloy frame/fork. It would appear from catalogs that these bikes were sold as complete with components installed and not available as a frame set only although I'm sure it could have been purchased as such. TSDI was a US distributor for Campagnolo, but apparently went deep into debt as their supplier later in the history of the business; may have been the cause of that business shutting down. TSDI owner was Thomas Eason (the name "Tommaso" is Italian for Thomas). Tommaso frames both aluminum and steel were all built in Italy to my knowledge; and I believe that the steel Tommaso frames were made by Guerciotti, but I have not confirmed it. The name "Tommaso" was merely for marketing purposes as it was never indicative of the actual manufacturer of the frames with that branding.