I'm working on a battle mechanics overhaul hack. I'll probably reveal more information once I'm up to about the Narshe split party scenario.
I dumped both scripts -- the Woolsey script via FF3usME, and the Slattery script via some other software, which I forget offhand (I've dabbled with a few.) I then copied and pasted over, line by line, formatting as necessary as I went. I actually had to go back again after that, a third time, when I chose to change my formatting. I'm still working through typos and other minor issues, and I think I have a formatting bug in the opera I haven't resolved.
I also have to use the old script for battle dialogue when testing, due to the new script using more space and thus needing to be moved. FF3usME doesn't like moved battle text.
Most of the menu work I pulled from existing documents, but refinding all of that would be a nightmare, and there are a few changes I had to RE myself.