I would by-pass the amp, but I would get the right harness for it. How much are you looking at spending on a HU? I have a Kenwood here that is still sitting in the box it is KDC-5023R it is not on the US web site it is a universal model I got on the RAF base in England. $140 shipped
MODEL: KDC-5023R
Plays disc formats and controls a compatible CD or MD changer
Removable faceplate flips down for CD loading
Radio Data System (RDS)
Multicolor wide LCD with white LED backlight
CD-R/CD-RW compatible
Multifunction key operation
Selectable key illumination (Green/Red)
System Q sound control
Built-in 50W x 4 amplifier
24 AM/FM station presets
CD-text ready
Random/repeat/scan play
2-way telephone mute