Im sick of the cd changer skipping in my sc400 w/nak, and decided to put in a mp3/cd player headunit. My question is, if i get the harness adapter for toyotas, will i need additional hi/low converters? Im trying to keep stock amp and speakers/sub. TIA

 

I also plan on buying the adapter from crutchfield.

 

bump. I forgot about the whole install, still need help.