Final Fantasy Hacktics

I feel bad posting a second question so soon after my other one. I tried looking through an Event Editor to see if I could figure it out on my own by looking at the differences between events but I am a moron when it comes to this stuff.
Is it massively difficult to change an assassination mission to a defeat all? Specifically I am talking about the final battle series leading up to the end. Rofel, Kletian, and Balk.

There are two parts to this:

1. Actually making the mission into a Defeat all Enemies mission functionally: You'll need to change the ATTACK.OUT file for this. Check out Raven's tutorial on this here.

2. Making the event say 'Defeat all Enemies': This is done by changing the event. When I did it in a patch, I just edited TEST.EVT directly, but I imagine you could use Raven's EasyVent.  From what I remember, I didn't have to change much.  I think you just change a number in one of the commands to change the text from 'Defeat X!' to 'Defeat all Enemies!'.  The events that include 'Defeat X!' usually have the person to defeat being highlighted in blue and fading out, so you might want to remove those commands from the event too.