If you move to one bodypart a day, I would increase the sets to around 12 per body part, or 3-4 exercises per body part at 3-4 sets. I do 5 day split, one bodypart a day, except arms I hit twice such as:
Back/Tris or Chest/Tris
Chest/Bis Back/Bis
Shoulders
Legs
Tris/Bis
I would hit a rest day in the middle of the split. Should work good for you, nice to hit a body part for a full hour, shred the s**t out of it. Just be careful on yoru recovery time so you dont overtrain, thats what I would watch for.