Good question and one I'm looking forward to hearing the answer from our sound system gurus here! I also wanted the JL Audio stealth box, but got the same answer...not compatible with the Sirius setup. So, I'm in the process of a workaround right now (and I do mean RIGHT NOW because the mobile installer is in my garage as I type this)...replacing all speaker components (front and rear) and installing a JL Audio 400w 4-channel amp. May install a sub at a later time...and when I don't have to haul kids around all day - they, unfortunately, do not appreciate mom's stereo volume.
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\'03 DreamCruiser #1040, too many interior and exterior chrome accents to list, orange/white underbody neons, SPICY PT 3BL and plate