I searched for this before I did it but didn't quite find my answer, so I'll post it and maybe I'll remember it in the future if I need any more work
And I may help someone else in need.
I have a 2012 Glee. I had previously installed the Eastern Beaver brake light adapter to run the Admore LED brake and turn signal add-on. Now, I got a Bestem T-Box 929 with the LED running / brake light upgrade. And yes, now there will be a good amount of warning to drivers behind me - still short of my goal of retinal damage to tailgaters - but I digress.
When you check the T-Box, the Bestem T-Box will have separate leads running from the lid brake light, and the LED lightbar on the main housing base. The factory installed hole in the base of the T-Box is small, smaller with the grommet installed. I considered replacing the internal wiring with uniform wiring, but then, for the sake of convenience I just used the wires there, but it's a tight pass to get all the wiring and shielding through the bottom of the box.
Once the wiring was routed out of the box, I grouped them and installed a 6 point Weather Pack quick-disconnect (QD) from Performance Plus Connection (I could splice down for a three prong connector as explained below, but I decided to keep each connection individual).
There are five wires leading from the Bestem (namely: large brown, large blue, small red, small green and small black). By elimination, observation, and luck, I figured that the blue is the lid brake light common, brown brake light hot, small red LED bar brake light, small green LED running lights, small black LED common.
In the recieving end of the 6 point QD, and tied to the Eastern Beaver wiring harness, only the red, black and white are used. Just keep the other wires insulated and away from the project at hand. I made black split into commons for the LED bar and the lid brake light, red split for brake hot wire and LED brake, and white to LED green (running light).
In sum here's a run-down.
Eastern Beaver black to Bestem blue and black (spliced into one or split on the common)
EB red to Bestem red and brown (joined as above)
EB white to Bestem green
This gives me a QD coupling between the bike and the box, and keeps it accessible for future work (maybe LED turn signals). The finish job was fairly clean and left enough wire length to make the connection without contortions.
I hope this helps someone, or saves some time!