Guilty as charged. I lined out one side of each of 933 & 1941 & used the mortal remains of BG Third 250 as a reference. The lines on 250's cream panels are rather less than 100% clear, but I interpreted them as being more Indian Red than Windsor Brown (the numbers are definitely gilt with an Indian Red shadow).
The shade I used was mixed by eye using A.S.Handover's flat Red toned down with black.
Pete.