Here's a link to a used battery box for the passenger side of your van. I bought one of these and hope to have it modified for the driver's side of my van soon.
https://www.ebay.com/itm/FORD-ECONOL...75.c100623.m-1
I also had screwy electrical issues with multiple cables stacked on the post of the starter battery. I found an "old-school" RV mechanic who installed a device that fixed the problems I was having. I doubt he used a schematic.
Auto parts stores have the door cables at much lower prices than a Ford dealership. I ordered mine online, but don't recommend it since it's better to see them in person to make sure they're the right size/length. There are also medal replacement ends for a more permanent fix, but the set I bought online were too large... Cheap, so I'm going to give them to the owner of a Ford F-150 pick-up rather than trying to return them for a credit.
*The screws in the replacement latch kit are longer than the originals, so they came through the back of the cabinet door slightly. I suggest you use the original screws or buy replacements of the same length.