My information says that the Italian threaded models were made with SL tubing by Romani. Given the number of other responses with BMZ, Korea, and Tom Ritchey, I'm led to believe that Palo Alto must have used a lot of contract builders. They did offer a Tange tubed frame in the 80s that possibly was English threaded. Lou Deeter, Orlando FL
"Never tell the Platoon Sergeant you have nothing to do."
- Unknown Marine Recruit