Changing Active Character slots?(FF6Adv)

So I'm going to admit, I'm new to hacking FF6Adv and have very little idea what Im doing.

That said, I'm trying to get Gogo in my party early on, which worked fine for the Magitek armor bit....buut as soon as the 3 party Moogle fight at the beginning starts, Cosmog takes over Gogo's character slot. I heard hex editing can solve this, but I have abolsultely no idea what I'm doing on that front. I've been able to find Gogo's hit points, but not sure what to do from there.

So I guess my questions are...
1. What's a good program I should be using for this?
2. How do I use the program to boot Cosmog and swap him for Gogo?

This is event editing. From what I know, events are handled the same way in the advance version. Here's where the moogles assignations take place in the SNES version. You could do a hex search in the advance version to find this part of the event. I know events starts at offset 0x7A0000. You could the use object $0D instead of the one that replace Gogo ($0B or $0C I'm not sure). A hex editor is required for this:

Code:

CC/A93D: 7F    Change character $0A's name to $0A (MOG   )
CC/A940: 40    Assign properties $0A to character $0A (Actor in stot 10)
CC/A943: 3D    Create object $0A
CC/A945: 37    Assign graphics $0A to object $0A (Actor in stot 10)
CC/A948: 43    Assign palette $05 to character $0A (Actor in stot 10)
CC/A94B: 7F    Change character $02's name to $12 (KUPEK )
CC/A94E: 40    Assign properties $12 to character $02 (Actor in stot 2)
CC/A951: 3D    Create object $02
CC/A953: 37    Assign graphics $0A to object $02 (Actor in stot 2)
CC/A956: 43    Assign palette $05 to character $02 (Actor in stot 2)
CC/A959: 7F    Change character $03's name to $13 (KUPOP )
CC/A95C: 40    Assign properties $13 to character $03 (Actor in stot 3)
CC/A95F: 3D    Create object $03
CC/A961: 37    Assign graphics $0A to object $03 (Actor in stot 3)
CC/A964: 43    Assign palette $05 to character $03 (Actor in stot 3)
CC/A967: 7F    Change character $04's name to $14 (KUMAMA)
CC/A96A: 40    Assign properties $14 to character $04 (Actor in stot 4)
CC/A96D: 3D    Create object $04
CC/A96F: 37    Assign graphics $0A to object $04 (Actor in stot 4)
CC/A972: 43    Assign palette $05 to character $04 (Actor in stot 4)
CC/A975: 7F    Change character $05's name to $15 (KUKU  )
CC/A978: 40    Assign properties $15 to character $05 (Actor in stot 5)
CC/A97B: 3D    Create object $05
CC/A97D: 37    Assign graphics $0A to object $05 (Actor in stot 5)
CC/A980: 43    Assign palette $05 to character $05 (Actor in stot 5)
CC/A983: 7F    Change character $06's name to $16 (KUTAN )
CC/A986: 40    Assign properties $16 to character $06 (Actor in stot 6)
CC/A989: 3D    Create object $06
CC/A98B: 37    Assign graphics $0A to object $06 (Actor in stot 6)
CC/A98E: 43    Assign palette $05 to character $06 (Actor in stot 6)
CC/A991: 7F    Change character $07's name to $17 (KUPAN )
CC/A994: 40    Assign properties $17 to character $07 (Actor in stot 7)
CC/A997: 3D    Create object $07
CC/A999: 37    Assign graphics $0A to object $07 (Actor in stot 7)
CC/A99C: 43    Assign palette $05 to character $07 (Actor in stot 7)
CC/A99F: 7F    Change character $08's name to $18 (KUSHU )
CC/A9A2: 40    Assign properties $18 to character $08 (Actor in stot 8)
CC/A9A5: 3D    Create object $08
CC/A9A7: 37    Assign graphics $0A to object $08 (Actor in stot 8)
CC/A9AA: 43    Assign palette $05 to character $08 (Actor in stot 8)
CC/A9AD: 7F    Change character $09's name to $19 (KURIN )
CC/A9B0: 40    Assign properties $19 to character $09 (Actor in stot 9)
CC/A9B3: 3D    Create object $09
CC/A9B5: 37    Assign graphics $0A to object $09 (Actor in stot 9)
CC/A9B8: 43    Assign palette $05 to character $09 (Actor in stot 9)
CC/A9BB: 7F    Change character $0B's name to $1A (KURU  )
CC/A9BE: 40    Assign properties $1A to character $0B (Actor in stot 11)
CC/A9C1: 3D    Create object $0B
CC/A9C3: 37    Assign graphics $0A to object $0B (Actor in stot 11)
CC/A9C6: 43    Assign palette $05 to character $0B (Actor in stot 11)
CC/A9C9: 7F    Change character $0C's name to $1B (KAMOG )
CC/A9CC: 40    Assign properties $1B to character $0C (Actor in stot 12)
CC/A9CF: 3D    Create object $0C
CC/A9D1: 37    Assign graphics $0A to object $0C (Actor in stot 12)
CC/A9D4: 43    Assign palette $05 to character $0C (Actor in stot 12)
CC/A9D7: 3F    Assign character $01 (Actor in stot 1) to party 1
CC/A9DA: 3F    Remove character $0E (Actor in stot 14) from the party
CC/A9DD: 3F    Remove character $0F (Actor in stot 15) from the party
CC/A9E0: 3F    Remove character $00 (Actor in stot 0) from the party
CC/A9E3: 3F    Assign character $02 (Actor in stot 2) to party 1
CC/A9E6: 3F    Assign character $03 (Actor in stot 3) to party 1
CC/A9E9: 3F    Assign character $04 (Actor in stot 4) to party 1
CC/A9EC: 3F    Assign character $0A (Actor in stot 10) to party 2
CC/A9EF: 3F    Assign character $05 (Actor in stot 5) to party 2
CC/A9F2: 3F    Assign character $06 (Actor in stot 6) to party 2
CC/A9F5: 3F    Assign character $07 (Actor in stot 7) to party 2
CC/A9F8: 3F    Assign character $08 (Actor in stot 8) to party 3
CC/A9FB: 3F    Assign character $09 (Actor in stot 9) to party 3
CC/A9FE: 3F    Assign character $0B (Actor in stot 11) to party 3
CC/AA01: 3F    Assign character $0C (Actor in stot 12) to party 3

I actually spent some time fiddling with Cheat Engine and did manage a workaround to the problem actually. I found where Gogo's saved, then put a freeze on everything on him. Once the time came to be replaced with Cosmog, the mass freeze kept it from doing it. I don't know if Cheat Engine is a proper hex editor, but it worked well enough for this instance at least.