Here is an idea you might want to consider if you would like to have a quick disconnect tour pack lighting instead of removing the seat every time.
It doesn't matter if it is an after market or a Harley tour pack or if you are using after market or Harley LED brake/tail/turn light bar it will work. It does matter if it is not LED. Then different wire harness will be needed. If you purchase a Harley wire harness then you will always have to remove the seat for connection. New to the site so I haven't mastered the trick to loading photos yet. Sorry maybe soon.
Here's what I did.
I put an after market king tour pack from hog works on my 17 SGS. I bought the LED brake/tail/turn light bar from TCMT On amazon and mounted to the tour pack.
I bought the king tour pack wiring harness from Bad Dad and another harness from Namz (NTP-CB01) On amazon (This fits your bike). I installed the Namz harness under the seat--ran it to left side under frame rail and out side cover and routed it the trickle charger wire and zip tied together. I bought a small rubber grommet that fits the tour pack wire harness only not the connecter. I drilled a hole on the left front bottom corner side of tour pack that fits grommet. I removed harness end connecter, ran harness thru rubber grommet and reattached connecter (Water Tight). Position re-attached connecter right under tour pack were hole is, hanging vertical leaving tour pack harness to snake in side. (Buy a Liner). Now you can quick connect or quick disconnect to the Namz harness without any free play of wires rubbing any where. Truly plug and play!