The sheep are unimpressed at the smoke show - the banker has one of those odd-shaped bars on the tender rear coalspace.
This slide has been a subject of great debate! The number is not 100% clear and it came as 43039 dated 1966-04-30. However that loco was always off Holbeck and never had a rear tender bar so it is very unlikely to be 43039. After studying the image I think the last digit is definitely a '9' so the next candidate was Tebay's 43029 but that too never had a bar. Finally we think it may just be Tebays 43035 but that was withdrawn in October 1965 meaning the number and the date was wrong on the slide! If anyone can help then please throw in your thoughts!
I've now seen a picture of 43049 off Kingmoor taken by Derek Cross in the Bradford Barton 'London Midland Steam in the Northern Fells' quoted as 'summer 1965', showing a tender bar, at Kirby Stephen East. It has the same filthy cabside with the numerals cleaned. Could this be the answer?

Another suggestion is 43033 which was allocated to Tebay at the time with the tender bar but the last digit looks like a 9 to me.