Add a sub to your factory monsoon and keep your 12 disc stacker . Includes both cables , line level converter into 2 rca's and seperate gain controls . This is all plug and play with ZERO choping of the factory harness and includes AOEM-GM21C harnes not just the OEM 1 .
http://www.go2pac.com/products/oem1.htm

http://www.cardomain.com/id/banddirector ( sroll down to see pic of both connecors together on seat )

75 $ cnd .