I'm so cornfused....Trying to replace ATF fluid.. Prius v (lowercase v)

Your pictures are all too close up to get a sense of surrounding areas, but I believe that your last picture shows the fill bolt near the passenger side half shaft that connects to the CV boot/joint, and the other, lower bolt is the drain bolt. Both with 10 mm hex holes in them.

Did you also buy the aluminum crush washers?

Make sure you loosen/remove the top, fill bolt first, before removing the bottom, drain bolt. You don't want to dump your transaxle fluid and find that you can't remove the fill bolt.

Using a short extension on the 10mm hex will allow you to get your wrench on the fill bolt easier because it's so close to the half shaft.

 

The other bolt with the 10mm hex hole in it with the 2-1 next to it is probably the inverter coolant loop drain bolt. Leave that alone, unless you are changing the inverter coolant as well.

 

Using a longer extension on the 10mm hex will allow you to reach the plugs from the oil drain flap without removing the entire cover. A breaker bar or similar long handle will probably be required because the factory over-torques the plugs. Leave the fill plug loosened but in place so that the fluid doesn't splash everywhere. A small cheap funnel can be squeezed into the opening to catch most of the fluid as it drains. A piece of clear tubing pushed onto a funnel will let you refill from above. Go slowly as you near 3.5 quarts of WS ATF and just stop when it starts to run out the fill hole. New washers, a reasonable snugging of the plugs, and you're good to go for 60k miles or so.

 

there's nothing worse than cornfusion when changing your oil.

 

It's best to remove the whole underpanel. I actually do that with every oil change, it gets easy. Wash the fasteners whenever you take them off, they'll last longer. I've marked up your last pic, showing the fill and drain bolts:



If you haven't got it, I've attached a pdf of the process. Also shows those bolt locations, torque specs, etc. It's from regular Prius Repair Manual, but I believe applicable to the v as well.

BTW: Toyota's bolt spec is shameful: look at the rust bloom on all those fasteners!

 

As mentioned, remove the under panel is best to make it easier on urself

 

The half inch inside diameter tubing might be too fat to fit into the fill hole. I think I went with 3/8 inch tubing, what you do is use a short piece of the 1/2 inside diameter tubing on the funnel, then fit the 3/8 inch tubing into the 1/2 inch tubing.