Regarding components in the back: I got to spend a bit of time in the back of a Volt cleaning up a mess from a cheap reconditioned wet battery that someone had put in one instead of an AGM one. It had puked acid out all over the trunk and I got to clean it all up. The unit with orange HV wiring going to it is the DC/DC converter I believe, and the unit with a fan on it, oddly enough, is the audio amplifier if I recall correctly. The onboard charger for the HV battery is behind a front quarter panel closer to the charge port is liquid cooled, I think.
I’m somewhat surprised you rolled with the kit’s included vampire clips- I’ve heard so many people say that they are just a bad idea. Apparently you don’t mind them?