Sorry, Eworld. I was waiting to see if someone more knowledgeable chipped in.
Let me see if I can help. First, I'd like to understand this. Your amps are two-channel amps, correct? Right now, though, you just have one channel from each running one of your front speakers?
I think that you're wanting to split the signal for each speaker into two lines so that you can connect (for each speaker) a line-level input into both channels on each amp and then bi-amp each front speaker.
Am I understanding this correctly?