Hi Jason
After fishing the check pieces out.
I couldn't see the difference apart from what side the racket was, so I seeked further advice at Edinkille who supply G & E. Check out the web site.
The plastic part is the same, yes – the difference between the two models was that the mechanism for the cheekpiece sits on the opposite sides of the ratchet plate that slides into the stock. The plastic part has undergone some revision over the years – the earlier versions had no hinged piece, that came in later.
No Black II or Black III cheekpieces for right-handed shooters any more, all long sold and replaced by the new Smallbore cheekpiece.
Regards,
Mick