Sub and Amp Help!!!

Okay so I am planning on installing a 12inch JBL Sub in a custom box that will fit behind my seats on my 07 double cab. Building the box myself and im not concerned about that part. Obviously I will need to have positive(With a fuse) and negative wires going from the battery through the fire wall to everything. I am keeping my stock head unit in place for the time being(yes i know it s better to upgrade, i will eventually). What all do i need to wire up the head unit to the battery and then to the amp and from there to the sub??? Do i need some sort of harness adapter?then how do I tie in my current door speakers to the amp and sub??

 

You'll need a LOC (Line out Converter) to get the signal from the stock HU to the Amps. Your stock HU will run the door speakers and the LOC will take the low signals and process it so you can use a sub with it. Later if you upgrade you can rip out the LOC and just use the RCA's that are on the back of most aftermarket HU's.

You don't need any special adapters for this but you'll be cutting/tapping into the stock wiring harness.