Stock FJ Cruiser headunit in 1st Gen Tacoma

I read an article about the installation of a Scion hu in a 1st gen tacoma, but havent found anything covering an fj radio. The factory tacoma radio and fj radio are both double DIN and appear to have the same wiring harness. I found an article, however, saying that with an FJ radio in a rav4, the sound was disabling when a cd was inserted. It was suggested that this was due to the hu enabling an external amp for cd playback. I was under the impression that the fj didnt have an external amp, unless that came with the "package 2" audio system option....

I've got one in the mail to replace my alpine. Ive always liked the factory look but want mp3 playback so I'm hoping this will work. Has anyone done this swap? It would seem like something that has been done

I'm assuming that the BLUE and RED squares are matching connections...