Here are a few images in a Google directory. Perhaps that helps.

https://drive.google.com/open?id=1-NlKoVTagnSY_3_eG51N1k3kL8gzDO6W

Im a little confused on one thing. I had a G grade at one point, extractor gun, and it did not have those levers embedded in the frame. If this gun is an extractor gun, refit for ejectors at a later date, why would the frame have ejector parts in it? In the G, the cocking hook pushed the extractors out to raise the hulls.