Thanks for this.

I would avoid the expensive stuff. The expensive stuff is basically relay and distribution block in one housing. When this breaks you have no option but to buy a new one. Which is very very expensive. Relays will fail, not often, but can and will fail with time. The distribution block will never fail. You want the two units separate and can easily diagnose and swap out. If you wired it up with the base all you need to do is plug and unplug to swap the relay. And check the fuse for individual circuits that may not be operating properly.

The 100-400 dollar distribution block is very very expensive "tailor" product for something you can build for 35 dollars. Amazon.com: Blue Sea Systems 5045 Fuse Block St Blade Mini 4 Cir-: Automotive and any automotive relay 40 amp will more than suffice. You can go with a waterproof relay, but those relay are larger. I ran this setup in all my bikes and my dr on my big trip and it never failed. It even took a swim a few times and crashed it multiple times and one time really badly. The electronics never missed a beat. Its also super easy to check and use standard automotive relay that can be easily swapped out. I have this set up on my my sv650s as well as other bikes I had in the past. The trigger wire is easily found from wiring diagram, typical bikes will have one or two, one up front and one in the mid/rear of the bike. (https://miles-by-motorcycle.com/136/photos/506/untitled/163415/untitled)

PlushParu(https://miles-by-motorcycle.com/157623) , possibly aligned with your interests.