Keeping the ghosts in battle after K0?

I'm making the ghost character into something else that follows you in the Phantom Train, kind of like Reaper in RotDS. I also want him to stay after battle even after he's been KO'ed. I do believe this is possible. I found this in the C2 bank at C2/493F, probably checks if the character is a ghost and remove them from battle if KO, zombie or petrified. Would a simple EA EA work, or is there something else to it?
Thanks!