97 mustang cobra, mach 460

Im installing a new hu into my 97 ford mustang cobra with the mach460 and i need some confirmation that the harness im using is the right one. I previously installed a hu into another 97 but used a line output converter to feed the amps. The stereo shop where i bought the cd player from said that i could use metra kit number 70-5700 and that i didnt need an output converter just a way to turn on the factory amps. Im wondering if this is possible or if he just gave me the wrong kit?

I ended up using the preamp signal, it was hard to find the connector as some people said it was out of production.  I was looking for the line output converter because i have used it before but had no time to drive to wallmart to get it.  Got lucky at one small shop that had the preamp adapter that feeds into the factory amps.

By the way the metra kit that was given to me at the original shop was the wrong one, but he traded me for the right one and then i had to find the preamp adapter on my own. I had no problems wiring up everything and it works fine now. Memphis im sorry that you guys at best buy dont know the right way to do this install, im not knocking on you but it kind of shows what level of installers can be found at your bestbuy/circuit city.  I knew how to install the hu from the beginning just didnt have time to get the line output converter because its a far drive to wallmart, so i was going to try an alternative(turned out to be wrong). When i did my buddies 98 gt with the mach460 best buy quoted him over $250 because they told him the same exact thing you said: need to rewire the car otherwise your cd player will not work with the factory amps.  As jstruckman said there are no airbag or abs controllers integrated into the hu, im an auto tech so i should know.