my girlfriend just got an 07 mustang with a shaker 1000 system.im putting in an aftermarket in dash navi unit.i see crutchfield offering a wireing kit with all sorts of extra plugs and wires http://www.crutchfield.com/p_127C2RF...Interface.html
do i need this or will this ebay kit work?http://cgi.ebay.com/2007-2009-Ford-M...item5add40a38e

do i need anything else to do this install?ive done stereo install before but the shaker system and ford systems are new to me in general

 

I would stay away from the PAC interface. You spend all that $$ on it and you may still need diodes and relays to make it work with your HU, I found out the hard way.
Get a cheap harness adapter for a Shaker system and a voltage regulator and check out this "How To" by TacoBill.
https://themustangsource.com/f692/al...w-pics-455116/

 

I just put in after market deck and when the radio first powers on after you turn the key you get a quick feedback noise wtf is goin on please help

 

The PAC harness is expensive, but takes the guess work out. If you're comfortable with adding diodes and relays you'll save $$$. I personally went with the PAC adapter and dont have any feedback, hiss or noise. Looking back I don't think it was necessary to go with the PAC harness adapter even though it made installation easier. It's just a ridiculously expensive harness.

As far as noise it's probably a grounding issue. I only experienced this after adding several amps and it went away after I re-routed my RCA cables and moved my grounding points.

 

The only reason I can see for getting it is if your head unit has the volume speed control like the shaker does , and most don't ...

 

Agreed. If your using the harness ground, try grounding to somthing on the chassis. Pico fuse blew in my HU so I had to ground my RCAs. May want to give that a try if nothing else works.