Ok, I watched a video and their hole was at 3:00. In any case, there were two half moon things that also have to line up with that hole. It was a total pain to get in, but I got it in and started the threads.
In the video, they had a custom socket to fit the cap. I didn’t get one, so I modified my cap for a 3/4” socket.
I can tell you it would have been impossible without that socket. (At least in the truck)
My problem now is I marked the cap as you (or somebody) said. When I tighten the cap the mark will not line up. If I back it off till the mark, it’s really loose. (I have to back it off 3/4 turn) I can’t hardly believe that’s right. I guess I’m back to researching a torque setting.