Help! Wiring Install for Leer 122 Shell, with pre-existing Hopkins Trailer harness

Hi Tacoma Gang, First-time posting here. I'm hoping someone can lend a little help. I purchased a Leer 122 Camper shell, with 3rd tail light, and internal dome light. Wiring leads to a "TAG" Fuse box, requiring Chassis input. However, this used truck is already fitted with a "Hopkins Taillight Converter". I'm seeing if the the Tacoma Community may assist with DIY information on how I can attach a harness kit from this fuse box to the open circuit of the taillight. It may seem like a simple question, but the trailer harness is throwing me for a loop, and some confusion. Here is a photo dump of the current presentation. Any advice is much appreciated. I already purchased this male harness to attach to the pre-existing TAG fuse box.

$16 PPW TAG Leer Century Raider #139280 Fuse Box Harness kit

https://www.amazon.com/gp/product/B07DVM7KQP?ie=UTF8

Thank you in advance!

 

Do you have a 2nd gen or 3rd gen taco? I cant tell from the photo, and I'm not sure if there are any differences between the wiring harnesses, but on my 3rd gen when I got my shell, I had to do some weird wiring stuff with my tail lights since I have a trailer brake on my Tacoma that is tapped into my brake light system.

 

I have a Gen 2 Tacoma, 08 Access Cab if that helps at all. Yes, Without the harness I'm sure it would be pretty straight forward, but the Hopkins harness is throwing me off.

 

Alright. I'm about to go on lunch, and when I do, I'll snap some photos of my wiring setup, hopefully, that'll help a little bit even though it's a different gen/system. From what I know about the Hopkins harnesses, I'm pretty sure that they're a stand-alone system(or at least the one my buddy has on his is a stand-alone system) so you might just need to pretend it doesn't exist when hooking up wiring for the shell, and just hook up the wiring as you would if there were no Hopkins on it, but I'm not 100% positive on that. The other possibility for it is that you get a splicer for the taillight harness so that you tap into the brake light system BEFORE the Hopkins, so that way the shell system is run off of the factory system, but the Hopkins is still 'downstream' and not affected by the shell system. I'm sorry if that's confusing as hell, I can see why it would be, but I can also scratch up a quick diagram of what I'm talking about by tapping into the brake system upstream of the Hopkins.

 

It definitely makes sense! So basically splice the wiring above the harness system, between the light and hopkins box, pretending it's not there. I mean, it makes sense. Thank you for your advice and input!

 

Exactly! Hopefully that works for you! Keep me posted with how it ends up going/working!!