Thanks to everyone in this forum for the Scion mod. I bought a Scion T1807 HU, I used the Castulucci instructions below and it took about 25mins. For those of you who are hesitant about drilling that second hole for the antenna, you can just bend the plate back. Thats what I did and the HU mounted just fine.
http://www.castulucci.com/projects/carpc/oemnaviaccess
http://www.castulucci.com/projects/carpc/oemnaviaccess