I have 2 Witcombs dated 1958 and 1966. The 1958 frame is no 17858 and has nervex lugs and 531 tubing. I bought it for £25.00 after advertising on the Cyclingplus website and rescued it from a scrapheap. It was restored by Mercians earlier this year and has mainly Campag (Record & Gran Sport) equipment. See attachment. The other was built for me as a 15 year old and is featured on the Witcomb page of CR. It's has just been resprayed by Mario Vaz in it's original red and white colour scheme. It again has a mixture of record and gran sport. I'm going tp post both bikes on the CR website shortly.
The frame has handcut curly lugs and plain tubing. I went to Witcombs to order the frame in 1966 where all their frames were hand built in a garage with a centre door in the middle. There was a brazing hearth in the middle with benches with a vice to each side
Geoff Carter, Derby.