Putting a subwoofer and amp in big truck

I guess it depends where you head unit is located. Mine is in the overhead console so I ran wires under the headliner and back to the sleeper and down the sides. You've got to be able to look at it yourself and figure it out

 

Just dont be like those guys in the beat up civics that sound like the truck lid is making its mind up whether to implode or shoot skyward.

 

I have the OEM Mats and they cover the whole area. They run a lot of wires under it on the new trucks. I ran my camera wires under it and worked great.

 

I have a Kenwood head unit in the upper console and a Kenwood 4 channel 125w amp at 6ohm Infinity, and a Kenwood 1000 watt sub amp into two Infinity dual voice coils taking 500 watts at 8 ohms (250 ea) in an enclosed sub box under the bunk. I ran my RCA cables from the head unit behind the wrap around and over the door, into the passenger side cabinet in the bunk. It was easy to do, but I imagine if you were an in dash that would prevent a problem. Maybe up the window pillar? I put the amps side by side on a shelf and experience has given me the knowledge to provide a ¾" x 1" board beneath each amps securement points to allow sure to follow underneath. I'm a previous truck I had them vertically on a wall but first and occasionally the main amp would over heat. I also power the amps from a Planet Audit 20 ferrad capacitor through splitters with 2g cables to the amp and 1g from the capacity to the splitters. Large 0g cables are through a hole in the floor directly to the battery box. The remote sense wire from the head unit, run with the RCA cables to the amps control the and activation of everything. The capacitor assures a continuous steady flow of power that eliminates distortion from sudden power demands and doesn't starve the truck of electricity either. I suspect it's easier on the alternator too.
Speaker wired to the front door reverse path the RCAs run and subsequently to the sleeper, I've just tucked them under the wall paneling in a small crevasse.

I've had this system for nearly 10yrs. This is the 2nd truck is been in and it's proven flawless.
I have this setup

 

Do it the right way and hide those cables

 

that was how the last one was, rub across and down by the sleeper boot,

been a while since I dabbled in audio stuff though, just an alpine head unit with infinity kappas in the truck now, and the right song comes on I still manage to crank it up plenty and watch the fuel guage go down with my foot on the firewall…

 

I’ve got an 03 FLD. I run 5 speakers total. 2 DS 18 6 1/2” mid woofers in stock overhead location (saws all needed at this point), 2 Focal tweeters in door pillars pointed to reflect off front windshield to give good sound stage presence. A Skar 12” dual 4 ohm voice coil sub in a vented box completes the set up. All run thru a Punch 150x4. Got a total of less than $1k in this and it just rocks.