Congrats! I should be getting my 2003 Ram this week, after almost 4 months of waiting. I too got the infinity system (intentionally) to use with my empeg. I currently had my empeg in my 2001 ram with infinity, and used the PAC (www.go2pac.com) OEM-1 adapter to install it. I think (hope) that they haven't changed the infinity stuff for 2003, but I guess I'll find out this week. It really is a nice setup if you don't want to re-do the entire audio system, the empeg + PAC is totally plug and play and can be installed or removed in about 15 minutes. Check out the installation photo albums on www.riocar.org and check out the one Tony did on a Dodge Durango with infinity - almost everything should apply.

Oh, and I'm installing my empeg where the head unit is, picked up an adapter plate (if they don't have 2003 Ram in their books, get one for a Jeep liberty, or even a PT cruiser). Looks very nice.. I'll post some details once I get the truck and get it installed.