What you need is a double din size deck. Pioneer is the only one right now who offers an after market 6 disc in dash changer. It's an awesome unit and runs around $1,200.00 It's model # AVH-PH6800DVDI have an 04 A-cab with a stock radio/cassette/CD player, and I wanted to get an in-dash disc changer. Where can I find those? How much? What size am I looking for in the upgrade?