I've read on various forums about people connecting the external speaker (not the PA output, the external speaker one) to the Aux input on the head unit to get better volume. I'm wondering if this is safe to do on the basic head unit + Satellite (i.e. not the touch screen models)? I read in the 520XL's manual that it's an 8 ohm 7w output. I don't want to blow up the Aux input on the radio. Any opinions on how safe this is? My kit is showing up from RCR on Monday and depending on whether this is a good idea or not will influence where I install it at in the Jeep.