I finally got my new 16g speaker wires run but I realized that I might not be able to connect them to my headunit. The unit I have is this one. I can't afford an amp right now because I have to buy books but is there any way I can connect my new wires to the head unit?

I remember seeing gauge converters somewhere but that doesn't even seem worthwhile, I might as well just use the old wiring. Any ideas?