how to plug an amplifier directly to the battery?

wow seems to be a little bit complicated lol, but thanks everybody to be very very helpful I will try the hole on the firewall because the method of tacomajason is too hot Thanks again

 

I went the same route as G-Sak, and I used 4AWG. It is an incredibly tight fit, I used some nippers to cut a hole in the side of the collar of the rubber grommet, then used fishtape to push through.
However, I would suggest doing it this way; it keeps the wire inside the engine area and straight to the cab. By going through somewhere under the cab, you introduce your wire to all the nasty stuff that gets flung up against the bottom of the truck, and has greater opportunities to get the wire cut up.

 

if you look at it, the wire is actually incredibly protected. the grommet is directly above the frame ail, so it is never really exposed to anything. ill take pics this weekend when i do it again on my new truck...

 

I'm getting my equip, know how, and balls together for my first install. Jase, I might be hanging on your shop smock strings a little. Do post some pics of that amp wire route.
Heck take tons of pics, please.
Jimi

Also seems you can separate the amp power from the speaker wires completely with that route.

 

There's no reason you need to do this. If you are worried about line noise by having the power wire run near speaker or RCA wires, it's a common myth. On the '05+, the truck has nice guides that run down the door channels and locks wires in place.

 

will do. my amps should be going in this weekend.