I think ultimately the identity of the A4 will remain something of an insolvable mystery but it can be narrowed down. The LNER built 35 streamlined pacifics, one of which was bomb damaged beyond repair. Of the 34 that came to BR in 1948, 8 were withdrawn prior to May 1963, 3,13,14,15,22,28,30,33. Oddly enough 5 went on the 29/12/62, it would seem that a major accountancy exercise at a very senior level removed quite a lot of steam locomotives including all the Stanier pacifics from the LMR and ScR. I suspect the reason behind this is buried in the archives at Kew if your sufficiently inclined, I'm not. This leaves 26 locomotives of which 9 had an A3 corridor tender, readily recognisable by the beading at the top of the sides and obviously not the one pictured, nos 4,7,10,11,24,25,29,32,34. The photographed loco appears to have a non corridor streamlined tender, the front edges of a corridor tender turn inwards which is not apparent but it is pretty grainy so I wouldn't be definitive. From the RCTS 6 locos had streamline corridor tenders. 9,12,17,21,27,31, which leaves 11 possible contenders and truthfully it could be anyone of them. Of those, 8 numbers 1,2,5,16,18,19,20,23 were allocated to Gateshead and 3 numbers 6,8,18 to Kings X, and bearing in mind that it was only a month before Top Shed closed and all Kings X A4s were transferred to New England, it is I think quite likely one of the Kings X trio. Two of them 6 and 18 were further allocated to Scotland for the 3 hour Glasgow - Aberdeen expresses which leaves 60008 Dwight D. Eisenhower as the possibility, others pics show it with the "right" tender and it was withdrawn in July 63 so its's condition for an engine a few weeks off withdrawal isn't wholly surprising. There is a lot of surmise on my part, I am open to correction.
Regards
Martin