BBCode replacement using Kier's Post Content Replacement Tool


Formerly MsJacquiiC
I've 100+ posts that have the following/similar bbcode:

[mp3=San Zeno by Zach Finch][/mp3]
What I would like to do is to tranform these bbcodes to how my new mp3 bbcode is formatted. Like so:
[mp3=]San Zeno by Zach Finch[/mp3]
So I'm basically switching the url to the track name and vice versa. I have Kier's Post Content Replacement Tool installed. I suppose the Quick Find string will be mp3=

So I'm looking for the Regular Expression and the Replacement String. Is this possible?

Thanks for any assistance!