From what you briefly describe, I would guess your camera has not been converted to Super 16. Once it has been converted, you can change back and forth from Super 16 to regular 16, but the camera must be converted first.
Make sense?
-Tim
Hi Tim,
Yes it make a lot of sense... my serial number is C166 and I think it's not been upgraded. I have the reg16 ground glass and I can't find the screw of the ground glass or the hole on the viewfinder. Where I can send my camera for the change? I live in Spain.