Strange, That piece is not on Scosche's website, but I did look it up on Google, was unable to get an install guide, but from what I can tell this adapter is meant to tie into the low voltage signal that the stock HU has running to the BOSE amp and give your RCA outputs for an aftermarket amp, this is special because most LOC will not work with these type of outputs from the stock HU. If you are trying to hook an aftermarket radio up and keep the rest of the system stock BOSE, you need the GMSR02 I believe from Scosche, or the Axxess GMOS04, which in my opinion is better for the same price. There are more problems you are going to run into using that adapter with an aftermarket than the speaker interface, you also need an adapter capable of CAN-BUS integration in order to get the aftermarket to turn on with the key.
