I'm a car audio noob and I want to rewire my sound system. I figure it can't be too ihard . A local (reputable ) shop did the install for me (8 months ago), and although it's ok, It's got a few issues. For a start I get engine feedback in my speakers, which I'm told is because they've run the signal and power lines down the same side of the car. On top of this, my HU atm is doing weird shit where it random turns off/on while I'm driving.

So basically, because of this, and because of my somewhat arrogant attitude of needing to know how everything works, I want to redo the cabling. At the same time I'll hook up my rear speakers to my HU (current not connected (thanks again local installer!!!).

So this is a pretty newbie thread, so heres some newbie question

1. Do I need to disconnect the battery for any of this stuff? I think I'm fine with most things but the part I'm unsure about is when it comes to when and how to disconnect the positive (+) terminal on the battery. I don't reeeally want to electricute myself.
2. Any tips in regards to the cabling? Is there, should I or do I need to insulate either the power or signal cables while running them down the car?
3. What's the best way to guarantee a decent ground?
4. How do you remove an Alpine HU (9831) from it's DIN?

Mucho Gracios