ok so i tried to do searches and couldnt find an exact answer so. im installing a D3 i got everything else hooked up except for whats mentioned above. I understand the bypass as far as removing the MUTE wire from the pin and moving it up BUT do i then just ground the other end of the MUTE wire ? and do i also ground the parking brake wire from the radio? and i know the VSS has to do with the dynamics BUT what do i hook the VSS wire coming from the D3 to? i have a 04 silverado not sure if that matters

as for the bypass yes, that's basically what you do.

Bypass is here, along with several threads in the D-Series Hacks/Mods section: http://www.avic411.com/forum/viewtopic.php?t=5684

As far as the VSS, I would try searching/posting in the vehicle specific forum, that's a pretty common vehicle so you should be able to find something there.