I dont have a good photo handy of my install, but attached is an earlier photo before I “tidied up” the install
I will try to describe some of the runs here briefly;
Promaster Engine Alternator Charging;
existing 70Amp fuse on starter battery to Victron Battery Combiner (in photo) to switch
Positive House Battery (in photo) Red;
Battery post to 200amp fuse on battery post to switch
Negative House Battery (in photo) Black;
Battery post to “battery side” of the Victron BM shunt / other side of the shunt to ground “chassis”
Other Wiring Methods of My System;
1) The Manual switch has 4 functions; All Off / House Battery On Only / Started Battery On Only / Both House & Started Batteries On
2) The Manual switch has 3 lugs; battery lug 1 / battery lug 2 / load (which goes to my positive charge bus)
3) My Positive Charge bus has a 30amp fuse & then the positive red wire to my DC Panel
4) I used the “Ground Side” of my Victron Shunt as my Negative Charge Bus (I only have a couple of rings on it so I did not worry about an individual Negative Charge Bus)
Bus / Bus Cover / Battery Fuse Holder / Battery Fuse; All Marine Grade “Blue Sea”
All my wire is marine grade “corrosion resistant”
Some of the items & quality of the parts is not necessary. For me I look at the cost benefit & make decisions - I even get some of the decisions correct in my mind.
I tend to “over build” as a method of insurance (real or false one either finds out or never does). I try to have 360’ forethought, but have many blind spots.
You will get loads & loads of information on this forum (we all have opinions).
If I ever build another van (& I intend to as I am going to use up & mile out my 2018 as fas as I can), I could literally build it in 1/3rd of the time I took (which in my case was about 5 or 6 months in my spare time “part time”). Research & Understanding is the key. Don't be afraid of mistakes as we all DIYers make them (heck the Professionals all make them & the good Professionals are expert @ hiding their errors)
IMO one of the biggest advantages of DIY is the knowledge you have once you have completed (btw you never are completed)
Welcome to this Wonderful Sharing Community & All My Best to You for Your Buildout !!