frustrating ... I have the connection between the three unclued and have all the extra letters both down and up, but can't connect the two - or see what connects the pairs ...
thanks xwordfan - penny had already dropped. Spent the longest time trying to find connections to Japanese wrestling .... very ingenious weaving of letters and numbers by the welcome new setter - chapeau to Turnstone
Got there in the end by looking up the entry for the theme word in Wikipedia. Connection with 26 just a tad obscure, at least on this side of the Atlantic.