Yeah, I feel you bro'! It turned out great though.
Isn't it possible to copy the textures in photoshop, from the cat that doesn't fit on to the cat-texture you want to replace?
When I edited my textures that was how I did it, In other words I edited textures that I knew fit, and pasted things I wanted on to it, to create my custom textures.
Or was that what you did?