Question, I just got a new TL base model. From what everyone says here, the tech package stereo is quite good. I'm seeing on Acura parts places online that I can buy a navigation amplifier for around $300. Is this a direct plug-in fit? It may be easier than going the whole new aftermarket amp route for more power (440 watts vs 275). I'm thinking installing that plus some better quality aftermarket speakers. Where's the amp located on these?