Some useful info in the Minimail link here:-
"The plates were usually embossed but some were indented (stamped from above – which we can also do)." - Minimail
What year is the Mini as the newer looking Chassis Plate does not have the 1965 Seat Belt Anchorages comply info and your old one does?
It was probably changed for MOT purposes so the tester can read it.
From Mk1 Forum:-
"Longbridge chassis plates were pressed from behind with a horizontal dash separating any digits that were spaced out. Although both Austin and Morris maintained their own separate numbering series, this style appears to have been used on anything made at Longbridge regardless of it being Austin or Morris.
Meanwhile down the road at Cowley the Morris plates appear to be *engraved* (not stamped it seems), and a diagonal slash was used to separate digits. The body style was then stamped on afterwards in-between the first part of the ID and the car number.
The question is, on the vehicles that were made at opposing factories did the 'in house' style prevail ? In the case of Longbridge it would appear so but was an 'Austin' Saloon when assembled at Cowley fitted with an *engraved* chassis plate (with an 'M' suffix of course), or did Longbridge send down a batch of it's style of embossed plates for assembly? It's fair to say the later is unlikely as Longbridge were not known to be good communicators with Cowley, but you never know ! Elsewhere it is quoted that Cowley plates are *stamped* and this may well be the case for some but early on it would appear they were engraved ?"
General opinion on the Mk1 Forum was that front stamped chassis plates stopped in about 1963 - 64 and then all Austin/Morris cars shared the rear stamped "standard" chassis plate but with BMC/BL anything is often possible.......
Edited by mab01uk, 22 July 2020 - 07:19 PM.