MGB model identification

In NZ, there is always vagueness as to the exact model when looking at date of first registration due to the shipping time as well as the other lags between manufacture and sale. I’ve never been good on the numbers after the first cluster, (I could look them up, but they never stick in my head!) but there is a simple sequence of changes:
(the year given is the “model year” – changes for any given year commenced late in the previous year, usually October unless listed otherwise)

1962 – 1963 – pull-out door handles and 3 bearing engine.
chassis no commences GHN3 ….., engine no. begins 18G….,
1964 – still 3 bearing engine, but engine no. changed to 18GA ….,
1965 – 5 bearing engine (eng no. starts 18GB …. ) but still pull-out door handles
1966 – 1968 – push button door handles but no synchro in first gear
1968 – synchro in first, but seats don’t recline. GHN4, GHD4
(N indicates roadster, D = GT body)
1969 – reclining seats, but still the chrome grille and the tail lamps still had
the two piece lenses with the separate chrome retaining rim.
1970 – black recessed grille and one piece rear lenses, key still on dashboard
Chassis no GHN5, GHD5
1971 – key on steering column, engine no commences 18GG …. (commenced Aug 1970)
1972 –18V engine number introduced (commenced Aug 1971)
1973 – 1974 – new grille with honeycomb centre (commenced Aug 1972)
1975 – 1976 early – rubber bumpers, light switch still on dash
1976 (late) on – light switch moved to steering column.

There are other detail changes within the above sometimes but these cover the main model changes.