DIY, its not hard, I didn't like any of the dual kits as all have both in the engine compartment which IMO is nuts..no room.
I used a painless good Samaritan system..been using these for years.
I mounted it in the back and ran the positive Bat welding cable back to it, ran ground to the frame.
Aires automotive batt holder and a springtail solutions rack.
Got the idea from Ben Hendrick he has pictures posted here
Jeep SILVER dos