When the running numbers were assigned to the original wagons, they were solely based on historical photographs - if a wagon had a visible running number and quirky graphical oddity such as a slightly smaller CIE logo, older electrical flash symbol, yellow solebar handles, it was included. If no photo of a wagon existed, it was not included in the list. Attention to detail was key, and I've no doubt that that attitude has not changed. There were no "gaffes" as you alude to, access to private archives and individual collections not available to the public allowed for that. Whatsmore, there was a proposer of the data, me, and an approver of the same data, PC, and endless hours were spent ensuring accuracy.