Ok, I have a 2011 eco screw xlt. Got the basic sync stereo. So as you all know, no bass at all. Bought a powered sub for back seat. Nothing extreme, don't need to wake the neighbors. I've hooked up many amps in the past, not complicated. But this firewall is fort knox. I saw posts about the grommet with nipple....I don't have that. Don't see a decent spot to make a hole either. Anybody else figure out a way thru the eco fire wall? Went with a 4 gauge amp wiring kit. And hi lo conversion harness to run rca wires instead of all that splicing.

 

Passenger side that hole is already there at least it is on my '13. I ran my old amp power wire through it was perfect 👌 my new power wire 2/0 welding wire not so much 😄

 

I tried that plug. I couldn't get my guide wire to get thru it. Where does it come out on the inside?

 

It’s tricky. I used a coat hanger and worked it in and down towards the passenger side footwell near the fuse box.

 

Also if I recall I had to cut a small hole in the insulation material.

 

I got past the insulation stuff. Poked around for a half hour, threw a tantrum, and rage quit. I'll have to try again later on. Atleast I know now that its possible. Thanks.

 

The biggest problem is there is a ball like thing under the harness right in front of that plug on mine. Limits my movements. Pita

 

I came in the cab under the passenger door. Even a grommet there.

 

I read that the angle is a bit much for the wire. No problems though?

 

The Lisle 61030 2-Piece Wire Inserter Combo Set is the best way to deal with running wires through the firewall. ($23.08 on Amazon)
You stab the end (CAREFULLY) through edge the factory rubber boot of the main harness, run your wires through this tool and when you pull the tool out, the rubber seals around your wires.
Sometimes (often) there will be an unused rubber plug in the firewall you can use and that's even better yet.