Hi, my previous post wasn't too informative so here goes. I want to replace the factory mach 460 cd/tape head units in my 96 mustang and use the factory amps for the stock speakers and add an amp and sub. Is there an aftermarket cd player that plays mp3s, has a high pass crossover for the speaker outputs and a low pass filter for the amp preout? Will this work when I need an adapter to convert the speaker level outputs to the aftermarket amp add on? What other options do I have to not send lows to the factory speakers?