Multiple Unit re-numbering

[euryalus]

I seem to remember asking a very similar question in another thread, but the situation has arisen again, in that I am trying to identify the three class '101' vehicles that made up set C814. As far as I can ascertain, the middle car was Trailer Composite No.59123, but I think the power cars were Motor Composite No.50335 and Motor Brake Second No.50319, which became Nos.53335 and 53319 respectively - I am assuming that when renunmbering took place the 50XXX series became 53XXX vehicles, the numbering sequence being unchanged (?)

 

[455driver]

Yes you are correct, in the 1983? renumbering only the 2nd digit was changed with the 50xxx becoming 53xxx and the 56xxx becoming 54xxx, the 5 and xxx remaining the same except in a few cases.