Thanks for the info.

My thought was actually to return the harnesses back to original so I could just unplug the radio and then plug everything together to get to my amps. Then use the new harnesses to plug into the factory ones and give myself new leads to wire to the 4-channel amp. The bows were not included with the boat, so adding them I would use a harness plug to use the factory wiring. Not cutting the tower wires, is the other harness.

However, after looking at how big of a PITA it is going to be to buy the connectors and pins all separate, your way is going to be a better option. Looks like t-taps are the way to go or just cut and splice longer wires to reach my amps.