Hi all,
I got a Kenwood Woox compact powered sub. I'm going to install it underneath my passenger seat. The wiring for the sub is in a harness(much like on an aftermarket headunit). Everything seems to be in order except I can't figure out how in the world to connect the power cable to the battery. Here's a picture of the connector on the end that's supposed to connect to the battery from two different angles.

I've never seen a connector like this and the manual doesn't really indicate anything, it also doesn't show any piece that I'm missing so I have no idea what to do. Can I crimp a regular O connector on it(that I run the bolt on the battery connector through)?Any ideas?
Second, if I'm going to use preamp inputs on the sub. I am gonna install the sub on the passenger side but I need some advice on how to actually run the cabling. I understand how to release the door trim in order to get underneath the carpet, but as for running the power cable to the battery, how do I get it through the firewall? I've heard there are some premade holes, but how do I actually run the wire through there, attach it to a bent coat hanger to snake it through or is there a better way? Also, can someone let me know where a good spot is on the passenger side. Lastly, if I buy high quality preamp cables and try to keep the power cable a few inches or more away from the preamp cables, do I really have to run the cables on opposite sides of the car? Any advice is much appreciated. This will be the first time I've installed any sort of amp(whether it be a standalone amp or a powered sub) by myself. In my old car a highschool friend fo mine did it for me and did an awesome job, but I don't talk with him anymore so I've decided to bite the bullet and try it myself. Any input is appreciated, especially regarding the power cable issue.
Edit-Ok I think I've determined that I just need to buy the appropriate sized slip on ring terminal and then I should be good to go. Is this correct? I still need some advice on running the cables though.