That's interesting info Kevin, details of the first workings appear to be quite sketchy. Do you know which sets entered traffic on 09/08/76? I saw 253001 was mentioned in the other thread, was it formed with its correct power cars (002/003)?
253 001 formed 43003/2, 41003/4, 40001, 42029/03/04/05.
253 003 formed 43007/6, 41007/8, 40003, 42009/33/34/35.
253 005 formed 43012/10, 41011/12, 40002, 42027/15/16/17.
No TRUKs delivered by this date. 40005 not available for traffic. 43011 awaiting Works (collision damage). 42010/11 in bogie test train, yet to enter WR stock.
3 sets were formed to cover the diagrams, 2 for traffic, 1 standby. 253 001/3 in traffic on first day.