Amplifier wiring diagram

Looking for a wiring diagram for my boat (in sig) it has the wet sounds amp and tower speakers as well as the Polk amp. I'm guessing the Polk amp runs the sub and the wet sounds amp the tower speakers, the head unit (clarion) the rest of the Polk mids and highs. I'm going to look at it again tomorrow and will reverse engineer the wiring but was hoping someone knew or could point me in the right direction. I'm looking to add a third amp to run all the mids and his and not the head unti (if I'm right about the wiring).

Thanks for any help offered, I've looked through our manuals and wasn't surprised this info wasn't there.