English Mk1 questions

[McDell Bros]

Gidday all,
We have recently bought an English built Mk1 UC and are well under way with the restoration. Unfortunatly the front armour with the serial numbers on it is gone. We have searched in the other two places for any numbers, both angle irons are clean and original but no numbers are present, any ideas as to the lack of numbers? Many parts are dated either 1940 or 1941 and all usual TL numbers are present. We have looked at several other Canadian & English examples and noticed that they all have the striking or chisel like marks all over the armour, what is its purpose and should it be present on all carriers? Ours has no such marks anywhere. thanks for any help,
Chris