Yes from the etec installation manual it suggests that the 50AMP fuse is part of the aux charging cable (which I now need to go and buy)
Thanks for your feedback, switching the positives looks like the right thing to do. I'll draw up a revised diagram tonight.
Any suggestions for fuse boxes?
Also, we are keen to independently switch all the electronics however it was not set up like this before and I believe the reason was that the two switches installed were not all the same type. I am wondering if within a single panel like these
it is possible to have one for the nav lights with three positions as opposed to two