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congratulations on a fine build!
absence of fluting on spider arms of chainset mark it as either Gran Sport model or first generation Criterium
[1970 catalogue page]
breath of flute suggests a product somewhat later than that shown on catalogue page
headset appears to be the Thomas D. Cross & Sons Ltd. model J -
judging by rear brake centre it appears Holdsworthy designed frame with Weinmann centrepull brakes in mind
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