I had already read excellent descriptions of others adding this module and the prior Piecha module so I was prepared for what needed doing. And I have done mechanical things on cars in the past. (used to have a 1972 VW camper with manually set valves and dual carburetors. I used to set the values and balance the air flow amongst other things)
But I was not prepared for how hard it really was. That carpet was REALLY hard to bend and move out of the way.
And the instructions say to unclip the lid of the box before opening it. Now if they had just said HOW to unclip the lid. I knew from others exactly where those clips were, but no amount of pushing with my sore fingers was able to get it loose. On hindsight, I think if you push in on the SIDE of the box toward the inside of the car, maybe the clip will come loose. I used brute strength.
Sweat was dripping off my nose by then. I put a finger in a hole in the top of the lid at the back and pulled on that son of a bitch. Broke the first clip latch and part of the top off. But it came loose

Then I was able to pull on the lip edge and get the next one off. By the time I worked my way to the front of the top, that edge was under a plastic box coming down on it from the front. So by this time I was pissed enough that I just yanked the thing up and broke off part of that end of the lid too.
So the lid comes off by unclipping it.
Then that pesky connector. Again I had read about pushing the clips on the side, etc. But by then my fingers were really sore and no amount of pushing and pulling seemed to loosen the thing up. And I wasn't sure if the little latches were to be pushed into the center of the plug or pushed outward from the plug. I tried both with no success. My fingers were sore enough I decided to use a little leverage from a screw driver. Immediately broke the end of the clip off.
After more swearing, I managed to get the other side a little loose. Then I just put a screw driver in the top between the bottom and top pieces and twisted it horizontally and the top managed to move a little. (I know even that description isn't sufficient for what it takes to get it loose)
Everything went relatively easy after that and I was pleased that apparently I picked the right red and black wires out of the bunch so that it worked first time.
Although the instructions didn't describe it, it was helpful to undo the bundles by taking a couple of the tape wraps off them. The instruction picture show the tape on the bundles and then the next pictures shows them gone. So I recommend undoing the bundles. Which of course is really awkward to do in that small space with that damn rug pushing on you.
I guess I am glad I bought the module, but it was much more of a pain than I expected to install.