IIS_OUT1 (Pin 34 of the 7705) is the standard pin for the digital out cards. IIS_OUT2 (Pin 35) is unused, but available on the mainboard at the last header hole next to the other signals for I2S used by the digital sound card. If I remember correctly, IIS_OUT2 does not contain any audio unless enabled in software. I think Shonky had programmed it to contain subwoofer output. So maybe it is possible with some coding to get full range sound including the tuner by just relocating one wire.

Anyone care to try?
Stu