I first noted this one on 3rd November 1978 passing HA, when it was still allocated to FP.
D1516 (47417) was new from Brush on 10th April 1963. Withdrawn in March 1992, and sold for preservation in December 1994. Currently in the course of a rewire, as part of restoration. Apparently the wiring of the two preserved locomotives is quite different, even though they are both in the 47401 - 47420 "Generator" group.
I first noted this one passing HA on Tuesday 3rd October 1978, the first week that I attended university, and indeed during Freshers' Week.