Thanks
I have a dual battery setup as well... it's a really nice mod and when done right (with a good ACR and LVD) gives you a lot of convenience and worry free luxury. Even with solar, you still need to store that energy somewhere. I enjoy having the capacity and the separation from the battery that starts the truck.
The solar is just a different type of tool to me... I kinda did all this stuff around the same time so I forgot what really came first, but after using the dual battery setup solar turned into something I wanted in the truck as part of my recovery kit. I love my 60 watt folding panel as it tucks away out of sight and out of the way.
To be honest I rarely use solar when camping because it's just another thing to setup and deal with. There are times I do set it up, like when I have active loads and I don't want to run the truck over the course of multiple days. It can save you a good deal of gas, but I generally drive the truck enough to not need it.
One of the main reasons I built and bought all this solar stuff was just because I wanted some solar stuff to tinker with. Its been fun and educational. I also thought it was just a smart thing to own for general emergency preparedness so I didn't mind the investment.
Here is what it looks like under the hood, at least in my V6 4th Gen.
I know it sounds a little ridiculous but these days I just "plug my tent into my truck" before going to bed. Anderson quick disconnects are your friend. I basically have DC power outlets inside and outside in various convenient locations. If I can't do this I would use my ammo can battery pack.
If you want to go down the road of building a setup, I high recommend you check out the Blue Sea ACR and LVD (Low Voltage Disconnect)
I did a write up on the ACR here.
http://www.toyota-4runner.org/engines-suspension-wheels-tires-audio-accessories/235010-blue-sea-acr-automatic-charging-relays.html#post2642084
Here is the LVD I used.
https://www.bluesea.com/products/7635/m-LVD_Low_Voltage_Disconnect
Sorry for the long winded post, but I do enjoy tinkering with all this electrical stuff so I wanted to share.