Thanks, thats kinda what I'm using now, I just used the Stinger 'Y' connectors splitting the rear channel, one goung to the tower (2 channel) amp and the other going to the boat (4 channel) amp. But my plan is to add another set of speakers on the tower, powered by another (2 channel) amp, So I guess I could just go ahead and 'Y' the front channel to feed the 'new' amp.
Here's what I have:
Alpine 9857 (with iPod connect)
PPI DCX 500.2 / Fusion 3-way Combos (tower)
PPI DCX 300.4 / 4 Polk Audio Momo's (boat)
PPI DCX 1000.1 / 1 - JL 10 W7
PPI DCX 500.2 / Polk Audio 6X9's (tower)