That black box looks like a relay for a PIAA fog light harness.
Looks like a mouse has been chewing the sheathing of several of those wires. I'd be on the lookout for other mouse damage to wires.
Looks like an old school glass fuse. And the (brass) terminals are exposed, likely to short out on something if not protected. That large red wire looks like it is extending power to the interior cabin, you should be able to follow it from where it comes in the firewall behind the glovebox. It...