Gen 8 install Garmin Zumo 595LM and usb charger using relay/switched power

Hello, I have a 2015 Gen 8 VRF800 that I am going to install a Garmin Zumo 595LM on. The mounting will be using a RAM ball mount on the triple clamp. I have a 5 pin 30/40 amp replay that I want to use so that I have switched power to the GPS. Also I have a USB charger/volt meter (the rocker switch look type) to install on the relay. My question is has anyone done this before and what problems did you encounter, what should I be careful of? Also I was thinking of using the number plate light as the trigger for the relay? has anyone done this and which wire is it? Have attached a picture of the usb charger (it have a volt meter in the middle) and the location I am going to mount it on the bike. It does involve cutting the black plastic fairing piece Thanks.

 

Have a look on this thread there are pics and details on the install on my vfr. Personally speaking I would store everything (usb) under the seat.

https://vfrworld.com/threads/installing-12v-accessory-power-fuse-block.58099/

 

That is interesting. I have wired in a relay and used the accessory plug under the seat as the trigger as a temporary measure. After looking at all the options I have ordered a Fuzeblock FZ-1 and DJ7045F-2.2 socket plug. This will tidy up all the wiring connections. I also have a USB charger on the bars with a quadlock for the phone. so there is a bit of extra wiring......