AMP wire install through firewall

Struggling to figure out where in the firewall I should run my amplifier wire. I don't want to drill but if I have to, where is the best and safest place to drill? Oddly enough I couldn't find anything on Youtube or the internet. Any help would be appreciated.
Greetings - did you ever figure out the best place to run your wire / wiring though the firewall ? I have to do the same thing, but running a wire to the battery. I have the need to add a second accessory outlet. I have it already - thought I might find a rubber plug or pass-through point somewhere under the dash, into the engine compartment.