Something I just noticed about what Brian said. I think I can turn the 3s one into a 4S unit if I use a wire and prong from the 2S cable. Anyone else done this? I think it could work.
4S-
3S-
I think I got it, I removed one of the wires from the 2S and put it on the 3S to make it 4S. I moved all the wires over except the first one to make everything line up. Is this right? Does anyone have a picture of one without a bend in it? I think I got it but someone please let me know if ALL the wires go straight across. I can't tell in the pic since the wires are bent.