Question: Changing a Battle Command to a single spell

If you want to replace mimic, you basically need to copy the code for one of those commands, change the spell index, then make mimic call that (either by copying it over the mimic code or copying it into free space and changing a pointer)

A little update on this.

I successfully was able to complete the initial task by means of altering the "Health" command. 
As a point of continuing my learning in romhacking, I also attempted to follow this direction with a new ability using the other method listed (quoted here).

I thought I could try replacing another command (this time GP Rain) to a spell (this time Empowerer). I used FF3usME to change the battle commands (which worked well), but attempting to copy the code for Empowerer and paste it over the code for GP Rain did not change the command. It simply caused the character to enter their battle stance, but with no action. The ATB meter then reset as if an action had occurred. Am I missing something? 

Again I find myself curious if maybe it would be simpler to find the pointer that points TO the GP Rain command and change it to instead point at the Empowerer spell. I have no idea if that would help, but it seems a logical next step to try. Those Command pointers (if they even exist) are buried somewhere in the code in a place I can't seem to find though.

Does anyone have any suggestions? My ultimate goal is to create several Battle Commands that are just spells without needing to enter a Magic command window. One character might have "Fight, Blitz, Muddle, Item", while another might have "Fight, Lore, Cure2, Item", and another might have "Fight, Steal, Haste, Item", etc. Doing so would require more commands than simply altering "Health" and "Shock" would allow. Thank you in advance for any help given!