Boktai Sprite replacement project help (GBA)

[xaimill]

I currently want to replace the Django and Sabata sprites from Boktai - The Sun is in Your Hands and Boktai 2 - Solar boy Django, with the sprites in Boktai 3 - Sabata's Counter attack. However I'm a total n00b when it comes to ripping. I already got hold of a couple of ripping tools but I'm having trouble replacing the sprites... mainly cuz I can't see the sprites with Unlz.gba. I get this on all 3 games:


or this


Any help?
I know it's not much of a big deal, but I like the Boktai 3 sprites better than the boktai 1 and 2 sprites.


Thanks in advance.