I have red a few posts and looked at the wiring diagram but I am unsure which cable to connect to radio speaker left/right ground goes (read more below) The wiring harness coming from the dash has the wires below and when I connect them to the Pioneer KB 81 ZBM 02 the plugs for the Ground for Left/Right speakers don't exist.
I don't have a ground cable from the harness to plug into radio left and/or right ground plug. Do I leave it as is? 
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| Harness | Radio |
| Purple/Black | Power 12V |
| Yellow | Power Speaker left |
| No ground from harness to radio left speaker | |
| Blue | Power Speaker right |
| No ground from harness to radio right speaker | |
| White | Power ant |
| 3 Brown/Black combined into 1 | Ground |
| White plug (Red/Yellow - Purple/Red) | White plug (Yellow/White) |
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