Hmmm... I doubt that's going to work for a few reasons.
1 - Since the artwork style is pretty different, I don't think the end result will match up very well.
2 - Neither character is drawn complete (it looks like I'd have to add half a body on one - and I'm not that good) and are in greatly different scale, severely limiting how I can use them.
3 - each one is pretty wide compared to it's height, and if I'm not mistaken, the S3 uses a non-scrolling, single screen wallpaper. That means I'd have to try to squeeze them together in a very narrow area.
Basically, I don't think that I could make them close to the same size and
make them fit on the same single screen without one covering most of the other.
I really hate not being able to do pretty much any request, but I just can see this one ending up successful.