On Up passenger, the signal box is just visible under the bridge.

My old 1956 shedbook tells me that 7914 , " Lleweni Hall " was allocated to 81D , which was Reading at that date , and she still belongs there in 1962; they've turned her out in sparkling condition , possibly not long after a spell in Swindon Works , as she coasts into Paddington with steam shut off and her injector in operation.
There are ten coaches in tow , an indication of the capabilities of these " Modified Halls " , well suited to tackle heavily loaded express passenger workings such as this seen here in this splendid picture .