I'm looking to install a sub and amplifier into my LS400, but am curious where people who've done this have run their power and signal lines. I have an aftermarket head unit, but want to put the amp in the trunk. What is the best way to run power a)through the firewall to the battery, and b) through the cab into trunk?

 

please search, your question has been answered in depth in several previous threads

www.lexls.com is also a good basic reference.