Needle decoding question

[Banditpowdercoat]

So I am new to Keihin needles nomenclature, but what I have gathered, and please correct me if I am wrong, it's why Im posting,
GG OEM numbers are N1xx like my 98 N1EC.
Yamaha is N2xx
KTM is N3xx

Is N being the tattletale of OEM? But my q is the other 3. Mostly the number. Is it compatable to Keihin Taper letters? eg 1=A 2=B 3=C?
Also read GG N1xx are triple taper where the others are single?

Trying to decode my N1EC and some KTM, like N3EG to std Keihin numbers so I can order some. It's much more availible to me to get std Keihin numbers than OEM in most cases.
Is N1EC = AEC
and N3EG = CEG?