ID Mystery Cache

With the event of the recent RubyShoos challenge cache, some cachers have been short of a two character cache. I have thought long and hard about this and this is my offering.

Consider the following sequential numbers:

1930

1936

1950

1971

1979

1993

1998

2002

2003

2005

2014

The code you require is: ABCDEFG

Cache can be found at:

N51 (C+F+A). (B-G) (C-G) (D-A-F)

E000 E. (A-F) D (A-F)

You can check your answers at:

Cache is a magnetic 35mm film pot.