Clean trade is where you want to be to actually sell. Not accounting for the mods. The only mods that actually increase value, in my experience, are lift kits, bumpers, tires, basically 4x4 upgrades.
So assuming the truck is clean, the asking price is more than fair. But you're saying it's...
Dealers that use kbb won't be in business for long. Nada is what everyone uses. If a bank processes loans based on NADA, i buy and sell according to nada. kbb is a joke.