i have a 03 ram 2500 with infinity system and i need to know how to pu a custom radio in it i tried it and no sound come out the speakers and i had the amp wire hooked up

 

I've usually found answers to questions like that at Crutchfield. Make sure to check out their forum links. I installed new speakers in the doors of my truck, but kept the factory dash speakers. I found that they wouldn't work with the amp lead, only through speaker leads. I guess the infinity amp requires a hi-input lead to work instead of the typical milliamp, RCA-type connection.