[rawfuls]

No problem, I like rambles!
They tend to briefly cover things I didn't know about..

What exactly are the crossovers, I know that it will cut the bass from going into the fronts, but is it a physical connection I need to make- or just a setting?

From the manual, it looks like I just turn HPF to 100mhz and yay...?

What's the guage of the wiring I should run from the battery to the sub?
Sounds kind of hectic if I'm trying to hide a rather thick wire through the firewall through the door sills (probably), and into the back..

The unpainted metal isn't an issue, there's lots of it behind the trim panels.

I turned down the bass like you said (I knew it would distort a lot when I set everything up long ago, but didn't think it'd do it that much), and the fronts don't distort as badly anymore.
It's still up in the air if I want to drop some more money on this car.. or if I should just keep saving... It's not much of an issue to be honest, just something that would be awesome to have.