A splendid picture of Stafford Road's 6005, " King George II " which shows that it was one of the class to receive new front frames incorporating the replacement inside cylinder block, the " giveaway " being the modified covers to the inside valve spindles and the strengthening plate welded to each side of the lifting holes at the front end, one of which shows clearly here.
I believe that this engine spent virtually the whole of its working life at Woverhampton on the Paddington duties, and I never saw it in Plymouth in the 'fifties, but Stafford Road engines rarely ventured that far West although they did sometimes make it to Newton Abbot !