I, too, am using the Carlinkit on the JT. Mine is a first gen., but the manufacturer told my that the electronics are the same for both generations: the 2nd gen. is just a sleeker package. They also strongly recommend upgrading to the newest firmware if you experience any issues.
I use mine in...
So I was adding full-range 3½" speakers in place of the 3½" tweeters in my JT today, and tested the polarity of the tweeters vs. the full-range speakers (JBLs, in my case.)
A word of caution: a 9V battery puts a lot of current through your speakers, and could damage them. A 1½V battery will...
I went with the Viecar...
It's worked out nicely.
Probably the only adapter that really makes any difference is the OBD Link MX+, at like 4X the cost of any of the others!
Not pinching pennies, going for simplicity. And I've read too many comments about things like the RVI charger not working properly, and running the toad's battery dead. The last thing I need is my auxiliary braking system to quit because the Jeep's battery goes dead. KISS
A diode battery...
They're MPPVs (Mutli-Purpose Passenger Vehicles.)
At least, that's what my old Wagoneer was designated on the ID plate.
The current vehicle is usually referred to as Gladiator, or Jeep.
But not, "Truck," (that's my SuperDuty,) and certainly not, "Car."
I was going to use the CoolTech light system, but decided to go with wireless taillights instead: I didn't want to chop into the Jeep's wiring harness.
As for the battery charger, you can simply run a wire from the 7-pin 12V contact to the battery on the toad, through a 15A circuit breaker, and...
I have a couple of different first aid kits, a fire extinguisher, an entrenching tool, some ratchet straps, spare bulbs & fuses, the Jeep Torx kit, gloves, moving pad, flashlight, a couple of other small things that don't come to mind.