Take your coiled Cigarette lighter adapter smartcord that came with your radar detector and turn it into a direct wire smartcord. DIY Instructions and pics below...
http://www.wrxfanatics.com/index.php?act=ST&f=53&t=22904&st=0#entry269397
http://www.wrxfanatics.com/index.php?act=ST&f=53&t=22904&st=0#entry269397