An amp and some aftermarket speakers are in the plans for down the road but right now I am just trying to get by cheap. Does anyone know offhand how low the factory head unit can safely handle? I thought about using resistors but it seems like that would consume the little power the factory unit puts out. That's what makes me think maybe some tweeters. If I could run some 4 ohm tweeters plus the Bose 1.9 and run them safely at 5.9 that would be great.