So the fit is perfect. Has a double seal o ring setup. One for outside lip and one for the nipple that actually goes into filler hole.
I'm not so happy with the tether anymore. There's just not a good spot to put it. I was originally going to use an existing screw which is under the blue plastic def indicator, but the tether will have to be really long and that will cause an issue when closing the door. Another option was to self tap it into the plastic with in the door.
I honestly think it's best to not put a tether now. I will leave the option and have the hole drilled out just incase one wants to, but I will more than likely not include the actual tether. It will have a magnet and kit will come with a piece round laser cut metal you double stick to door so the magnet has a place to stick( OEM door is plastic).
It will say Eco diesel on it as well as be anodized green.
I will find out soo how much it will cost.