I am working on a step-van that has easily a dozen aftermarket electrical accessories. The electrical system "evolved over the years" and is a total mess, and there's an electrical drain that kills the battery. So I'm trying to redo the aftermarket stuff.
One of the annoyances is a very long positive battery cable down to the starter. Two other lines also go down there - the alternator and the "everything else" line, both with fusible links.
There is a nice location about 15" from the battery where I'd like to put a positive junction post, and bring in the line from the battery, a new, better-routed line to the starter, those two other lines, future aftermarket device connections, and cables running to front and rear bumpers for connectors for jumper cables.
I'm wondering - is this a thing I should be doing? Is it a mistake?
I would also like to have a battery shut-off switch, but I see no reason to switch the heavy starter and alternator lines (GM 3-wire alternator) - I just want to switch the loads. I want to do this with a professional and permanent installation. Is this a mistake? I hear a lot about the importance of putting shut-off switches on the negative battery terminal. Does that apply here, or not? Switching the negative would seem to force me to switch cranking current, and I'm not worried about current leakage from the starting motor.