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...
https://smile.amazon.com/gp/product/B01MTKSCEJ
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!
Other vehicles...
The wife: 2015 BMW 335ix
2006 MB CLK 350 cab.
Me: 1966 Ford Fairlane
1995 Mustang GT convertible
1972 Jeep J4000
2006 SuperDuty
Plus a couple of motorcycles.
I’ve seen many posts in RV forums where the chargers simply don’t work, leaving the toad’s battery dead.
I haven’t seen anything about actual damage, either.
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...
Another vote for the Maximus Tow Loops.
Once I get some warmer weather here I've a pair to install on the JT.
I like the idea of minimal modification to the toad.
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.
Kevin
Scroll down to the bottom of this page and check out some of the other threads regarding this topic.
As for myself, I just added LED replacement lamps, and am quite satisfied.