Anything and everything 2000/2500/2.5.

My GT6 has a 2500cc engine from a Triumph 2.5pi Mark 2 saloon. The engine number is: MG83602E
I wonder if anyone on this group could advise me of the year that the engine was manufactured?

The car (2.5pi Mk2) was produced from 1969 to 1974 and then in 1975 became the 'facelift' model.

The reason that I am so interested is that the ignition timing was:-
1969-1972 8 degrees BTDC
1973-1974 2 degrees BTDC
and I wondered which year mine was?

Thanks for any help....

Mike