This pretty much the same configuration and components I have things on Big Red, but hopefully with lot less wire and colorful rat nests in conduit because I am mounting everything in the bed and not building it over 15 years as technology and knowledge evolves.

For simplicity's sake, I thought about powering the exciter wire on relay that connects between the starting batteries/alternator using a switched up-fitter switch, but I think I will just monitor the voltage on both the alternator/starting battery and solar using diodes (as electronic check valves) fed into the XY-60 voltage monitoring unit.

When either the solar or alternator is throwing out a mimimum of 14.1 volts, it will close the relay, and open the relay when the voltage drops below 13.1 volts (or whatever I set the XY-60 to). This way, when the truck is on, it will always charge the camp batteries, and when the truck is off but the solar is producing ample power, it will dump some of the extra power back to starting batteries during prolonged periods parked or at camp. With dual starting batteries on a gasser this less essential compared to the old rig, but batteries like to be trickled regardless when parked for an extended period. There is reason I could turn the key on Big Red and it started up with ease after being parked for 3 months. 

I didn't include the various fuse blocks in this image, but everything will be properly fused. For the CB radio, I will just tap the upfitter harnasses off the starting battery on a switched upfitter switch. Also will include a shunt and amp meter for monitoring the input from the solar, as I'm always kind of interested in watching that.

In the future, I do want to add a second solar panel, and swap one of batteries out for lithium ion, but I will keep at least one lead acid for cold weather charging. But that needs to wait, as this project is starting to suffer from cost disease, though I am reusing 95% of electrical components and wire from the other truck. 

By late summer, I want to add a cellphone booster and in late autumn add a line to use with a diesel heater for winter camping. I concede I won't have enough battery storage for the glow plug of the diesel heater, but the truck has remote start, so I can just double click the remote start button before starting the glow plug on the diesel heater. 

Also in the out years, I may want to add a portable refrigerator. They do use quite a bit of current, but especially if I add a lithium ion battery, this could fit into the set up without lot of additional change.

Mom got this for me, and he's sitting behind the back seat, keeping an eye on everything going on from the back seat.