No formation details found.
A Class 117 with a Class 121 DTS on the front (which seems to be W56287) seen at North Acton on 12.9.70 from the London Terminals Railtour as it crossed the Great Western Mainline from Paddington to the West. George Woods.
Pressed Steel DTS W56287 with bubble 55030 at Windsor & Eton circa early 1970s. Graham Clark.
Do you have any images of the set you can add?