Oh yeah, you can break the posts. I've done it.
The arm holder is an easy fix. StewMac makes a Schaller replacement arm which is better than the Ibanez in my opinion. You would get the part that attaches to the trem and the arm. It's a screw type though, more like a floyd. If you want the same kind that just pops in, you can just order a new arm holder from Rich at IbanezRules.http://www.ibanezrules.com/parts.htm#Trem_Parts
He's pretty good about emailing and directions, so if you order the part, he will tell you how to replace it. It's easy. About 5 minutes.