wire harness for after market radio (92 mustang)

[outlaw163]

well i bought a wire harness to connect my kenwood radio. i bought the harness from circuit city and the thing is it looks only way i can connect the harness to my aftermarket radio is to cut off one side of the connectors. it goes from one plug and seperates into two of em so i was thinkin on cutting the side with the single plug... any ideas well be appreciated

and how do i pull out the factory stereo


thanks,
steve