I found the relevant connector on my Vee. It’s under the back of the tank and I was able to access it without unbolting or lifting the tank or anything else. I’ve now installed Bigpie’s fuse box. I’d post photos but I can’t work out how to do it. Sorry.
It’s a lovely bit of kit, but I’d like to waterproof it somehow. It needs some sort of tight rubber cover that can be stretched over it. A condom would work perfectly (!), but before I resort to that I’ll do some research for less risqué alternatives. I won’t push my luck by asking for suggestions!