Double Din install question

[mikesz]

I am trying to wire up a double din radio (Chinese) to the matra adapter which has 4 rca plugs. I assume these should plug into the audio outputs of my radio but I don't have 4 audio output jacks on the back of my radio. My radio only has 2 audio outputs for rca type plugs. the radio harness does have several audio outputs that are regular copper wire. Do I need to get an RCA adapter to solder up to the wires coming out of my radio harness? if so what should I look for?