Just as I remember, besides some color change models. There was some early F75's that you could get in camouflage color.
F75 original, shaft was gold in color and there was no boost processor (Bp)
F75Ltd (SE), color was black and it had the (BP) boost processor.
F75Ltd 2 (DST), color black and it has the DST select-able on or off at start up, and the added FA processor.
Then the upgrade which could be any of the above models upgraded to the F75Ltd 2 (DST)
So in some cases the only way to tell which model, is to turn it on and see what it has, or like was stated, you could call the factory with the SN and ask.
To me it has always been a mess, could have been F75, F76, and F77 or what ever.
If I missed any, somebody jump in here.
Ron in WV