So I'm trying to replace the rear speakers in my '95 B2500 van and I'm a little confused. I'm replacing the stock Infinitys with Polk DXi 691s, but I don't see an obvious way to connect the old wiring to the new speakers (pics attached). Could someone help get me started? I have access to all the tools I could need, but I haven't done anything like this before and I'm a little lost. Any advice would be much appreciated!