I would have to look. I don't remember which hole it is in. I don't think it really matters. Which ever one is easiest to get to.
I also got an oil pan heater, for better oil flow and it it warms up the engine even more. Also a battery blanket so the battery isn't as sluggish on the really cold mornings. Since you have an automatic, a oil pan heater on it probably wouldn't be a bad idea. I have one on the 2019.
I have a themocube for cattle water troughs on the outlet the heavy extension cord plugs into. That way it only turns on when it needs to and shut off when it's warm enough that they aren't needed. No point in burning electricity if it isn't needed.