Audio Systems: Car Audio, gmc seirra, car button

Question
hi i just bought a 2005 gmc seirra extended cab. i want to put subs in it. it has a 6 disc cd player. it has xm and onstar and controls on the steering wheel. what is my best bet. i was thinking about installing an aftermarket cd player but i dont know what to do about the onstar. i thought about puting a new cd player in and leave to stock one in and run the subs through that one. if i put the after market in will i have problems just taping into the stock speaker wires. thanks, matt

Answer
I would go to www.crutchfield.com and use the "what fits my car" button and fill it out.  they will provide you with the options for wether your car has onstar or not and provide options for "patching" you in.
Let me know how it goes please!
Good luck!