Re: RG 3120 twilight prestige tremolo arm holder repair?
Not sure if it will help, but a 2001 guitar most certainly should not have an Edge Pro on it, unless it was fitted aftermarket, which seems extremely unlikely. The Edge Pro wasn't introduced until 2003. More than likely, you have a Lo-Pro Edge. That being said, I think the arm holder may be the same on the two bridges since I believe the arm is, in fact, the same.
Other than that, I'm afraid I can't help, just want to make sure that if you do end up looking at a new trem, that you're looking for the right model. Lots of unnecessary confusion out there about Ibanez's naming schemes for its floating trems.