According to Roy Bacon's book 'Triumph Twins & Triples' the T100A from Oct. '59 was "All black finish, lower petrol tank ivory, usual parts chrome plated." (although a build date of Oct. '59 would suggest a 1960 model year machine?
If the T100A model was built earlier (as a '59 model) I couldn't say, and there's no mention in his book of a different colour scheme (which changed for T100A in Oct. '60 to "...black tank top and silver lower, the silver also being applied to the front mudguard and rear enclosure. The frame and forks were in black..."
If your T100A has an engine/frame number between H5485 and H11511 then that should make it a 1959 model? If the number is somewhere between H11512 and H18611 that would suggest that it is a 1960 model?
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Update
I just checked through your previous posts as I remembered you asking for some 'T100' date info previously, and if the engine and frame are the 'T100A' ones then the frame appears to be early 1959 so may not originally have come from a T100A, although the engine could be? That doesn't really stop you painting it up as a T100A though.
