Having last commuted regularly from Waterloo in the early 1990s my memory is slightly faded - that plus the many beers consumed in those days as a young single man! I seem to recall that one 455/8 had it's DTSO replaced (either permanently or for a short period) with that from a donor 317 or even a 210. I could be wrong but I'm fairly sure back in the 1980s/90s I saw a mismatched unit at Waterloo as I recalled remarking that the windows didn't have the usual "hopper" design. It was in the original BR blue and grey colours, although in fairnesss I couldnt say if the regular colour scheme had changed to NSE at that time. A bit vague I know, but the usual google search hasnt brought anything obvious up. Can anyone shed light on this and reassure me that I didn't just imagine it?!