What are you trying to do? Are you planning on using the OE outlet or will you run wires from the front? The reason I ask is the rear outlet is pretty weak IIRC... 10amps or something like that. That means you'll be limited to under 1000watts. If you need to 'go big' you'll need to plan on wiring from the front in which case the closer to the battery the better. The high voltage AC power will travel to the back with much skinnier wire and easier than lots of low voltage amps.
:cheers: