nelson "version" question
OK, so SS and LS are pretty self-explanatory.
I have a grand total of ONE Nelson Q40 engines, acquired in various trades. I was thinking about dabbling in Q40 just a bit. I know it's a SS, the original owner had it before the LS ever hit the scene.
However, in an online auction the other day, I saw this heading:
NELSON Q-40 SS with latest good case
How does one without a background in the Q40 Nelsons know what era case one has? (I've had SS Nelson Q500's and even before that, Nelson .15's (QM)- but not enough of them to know how one knows which is the "latest good case"...)
Just curious, that's all.