My mid-term solution is now fully in place.
The dual battery solar charger is in the tool compartment of the Beach boot. An Anderson lead is connected to the Starter Battery terminals of the solar charger.
Power from the solar charger to the Starter battery exits the boot via an extension lead.
The extension lead is held in place with little utility bolts I already had for holding the roof topper in place, and enters under the van’s bonnet.
The extension lead plugs into the starter battery via a permanently connected Anderson socket.
Not much to see here except evidence of the terrible state of our starter battery. The van had a good run yesterday yet already the starter battery is showing only 36% to 61% capacity. When the solar charger is actually recharging the starter battery the indicator shows 3 bars indicating 62% to 86% capacity.
To drive off the extension lead needs to be removed.
Once the system has been thoroughly tested we will replace the starter battery. But real-life testing will be with the old battery.
This is a mid term solution.
The long term solution will be to hard wire the solar charger to the engine battery via connections under the front passenger seat.