Someone recently asked me how I modified Sephiroth. I will also post my answer here, so that others may give it a try.
"Seph in the final fight uses 'mu' files, while the other Seph uses the 'sa'. You're right, I used a combination of the high res and regular files with Seph, also using the Seph patch to play him as the main character. When you switch in the high res head, you must also switch in the high res eyes and mouth texture. I also used the high res legs, but I had to scale them in Milkshape to make them fit under the cloak. Finally, new files must be 'padded' to match the old files, if they are smaller than the originals. This is done by using a hex editor and inserting lines of 00's at the end of the file, making it larger. Otherwise, your battle.lgp will be corrupted. It is okay if the new file is larger than the old one. This seems to work fine.
The sword I have him using is one I designed myself, after a sword in my collection IRL. I took the original model for the Heaven's Cloud sword, scaled the gold chains on it down until the game would no longer render them, narrowed the blade by about half, keeping the original length, reversed the handle so it would have a pommel, changed the color of the grip to black, and extended the base of the blade to make a cross guard. It is now a more traditional Germannic hand-and-a-half sword. I was able to make these modifications using Milkshape (shareware), after using one of Alhexx's programs to convert the model into RAW format.
It may seem like quite a bit of trouble, but for true fans of Sephiroth, such as we are, it's entertaining and well worth the effort. I would send you my battle.lgp, but I've made many other mods to it.
I hope you will give it a try. Good luck!"
