Just a thought on where to hide the trickle charger connector once you've hard wired it to you bike. I noticed there was a hole on the underside of my tank console's leather pouch, which I only use to stash a small cable lock for my helmet, so figured it would hide away nicely in there...
Just put the wires through the underside and underneath the tank to the battery.
Wires tuck out of the way of the seat mount.
Plug into charger when required.
Out of sight when not required. Well, it works for me.
mine is left side near oil tank frasers at newcastle fitted mine do not recall how much, nice job