I successfully replaced two Edge Pro IIs with Original
Edge trems. The Tail portion of the cavity had to be extended to accomodate the lock screws, and I had to clear the front corners by the posts to clear the fron portion of the wings.
I'm going to be doing an Edge III to Edge retrofit in the somehwat near future. I will post my findings.
Please note that both of the swaps I did intonated perfectly for A-440. I don't know if there is enough travel to intonate for other tunings.