I don't wanna hijack this thread, nor do I want to showcase my ignorance, but...

if you want to maintain the factory speakers ... you will want a very low wattage amp

I was under the impression that the speakers were the ultimate arbiters of how much wattage was passed to them. That is, the speakers might never ever use more than 30W of power, and, therefore, slapping a 400W amp back there wouldn't do any worse or better than a 30W amp (ignoring quality differences between the amps).

Am I wrong in this? The reason I ask is that while cobalt might not want to replace his factory speakers now, he might want to do it at a later date, and if he did so, then he might have to get a new amp, as well.