[Z4NJ]

Anybody know how or where to find the instruction to install z4 aftermarker stereo" step by step". Well bought kv819dvd, wire harnees, and antenna adapter. My system is 10 speaker "Hifi". I just can't figure out how to connect the aftermarket radio 4 speakers wire to the 10 speaker with manifucture amp. I read couple forum saying you have to install new aftermarket amp and speaker. Is there a way to install with out buy new amp and speaker? Please HELP!!! Instruction step by step is very helpful. THANK