Just bought '98 Z3 roadster. Verified that the radio is indead weak as noted in other forums. Bought new Alpine head unit with built in amp and a separate 4 channel amp. Figure that gives me 8 channels of reasonable power to drive most of the speakers in the roadster. Turns out it has ten speakers if you count the two in the subwoofer. Maybe I will just ignore the two little ones behind the seats for now. Other option is to replace the kickpanel "woofers" with full range speakers and eliminate the separate door midranges. I guess I would keep the door-mounted tweeters. Will now spend some time pondering how to get it in and wired up. Any body else done this or have suggestions?