OK, I've got a question which I have gotten a couple different answers for, so I'll pose the question here: I have a 2004 Mach 1 with the Mach 460 system in it. I want to replace the head unit with an Alpine CDA-9855, but keep stock speakers / amps for the time being. Went onto the Crutchfield site, and they said there was no problem, they provide a wiring harness so its plug and play. I know that other people have said that there are issues, so I tried the Crutchfield website saying that I have a 2001 & 2003 Mustang. In this case, they say that the head unit would be a modified installation and that aftermarket amplifiers would need to be used.

My main question is this: did Ford change something when they went from the 03 models to the 04 models? The only difference that I know of is that the 04 head units are satellite ready, but did they change other aspects of the system as well that would make the head unit replacement simplified?? Any insight would be appreciated.

 

Here This may not be exactly the one that will fit your application but thats basically what you need. It takes the lines that run to your 460 amplifiers and converts them into rca's that 9855 has front, rear and sub rca outputs so you'll be good with that. I have it in my car and it works 100x than that output gain control adaptor thing.