Diesel Bombers - Well, time for a new truck

So, we've out grown the current tow rig. Meaning we don't all fit inside anymore.

My dilema is trying to figure out the value of my truck.

Book is low, and I know it should sell for more than that.

Truck is in my sig, and has 118K on the odometer.
Runs flawless, and is one of the cleanest you'll find. Interior is really nice. Less than 10K on the new ATS trans.
The ONLY reason I'm selling is because I need more room. I'm really not wanting to, as it's a nice truck. But, I need two tow rigs like I need a hole in the head.

Any ideas?

$12K? Maybe a little more to the right buyer that realizes the value of a good setup?

Only pic I have:
Attachment 44182

Has a stage 4 ATS trans, #100 fuel plate, Amsoil intake, 4" exhaust, 16* timing, Isspro gauges, Mag hytek rear diff cover, 3K GSK, mild pump tuning. All the basics.
Link to trans details: 47RE Stage IV Package - ATS Diesel