Now you can see the tee and the space where I was holding the camera for the previous spot. Also notable in this shot is the long run of *flexible* CSST. This becomes important and useful for the last part of the installation as you'll soon see. See where the CSST turns "right" and exits the frame? I'll need to make use of that "slack" to connect the rigid iron pipe.
This is where the CSST "exits, stage right". Kinda. Exits the frame of the photo; the line runs all the way to the cas meter/source of course.
I drilled through the floor in the kitchen as close to the wall as possible. I chose this lateral location after measuring and I picked something between the joists. I picked the vertical/toward the wall location because the back of the oven has a brace all the way across the back bottom that, the valve will not fit underneath. So, I want the oven to be as close to the wall as possible, that means the pipe needs to come out of the floor as close as possible. Then, I dropped a thin piece of wood into the hole (as vertical as I could manage) so I'd have something to measure to once I went back to the basement.
Back in the basement. This is taken from up in between the joists with the top of the camera hard against the bottom of the floorboards. You can see the lower end of the stick from the previous picture. It's gonna be difficult to get a pipe wrench in there.