Running wires behind the dash
 

i feel stupid asking this but, how do you run say a 12 gauge power wire behind the dash board? i have a few switches and such that i want to power and am running them off of stock wires. But i want to add a few more things and i don't want to continue chopping wires because i don't want to mess with stock electrical obviously. (if my writing is a little hectic sorry, its almost 5 am and i'm still working on stuff for work) i have 4 gauge wiring running from the battery back to my amplifier.

Do i need to just run it from the battery to the dash or do i split from my 4 gauge wiring somewhere and if so where?

thanks guys

i got 3 switches in the roof mounted console. i have a switch that is located in the seat belt holster. i have a sub switch that is for the sub and 4 gauge run under the plastic on the sides to my kicker. i also have 2 gauges on the pillar. to power all this, i found a hole that i drilled out more. got some weird sticky rubber stuff from home depot and i ran wires through firewall. under dash and routed from then on. and use rubbber stuff to seal hole. i have the wires routed in the headliner to the switches up there. its always easy to tuck wires under the dash or under carpet than physically behind the dash.

FYI, any time you run new power through the firewall make sure you protect it with a fuse. If it's connected to the + terminal on the battery you should have the fuse no more than 18" from the terminal. Without a fuse it could short out anywhere along it's length and cause a fire.

Also, make sure you use a rubber grommet where it goes through the firewall to stop it from shorting out there over time.