Yaris gearbox fluid replacement

[Carlo]

Hi I'm seeking advice here if I may? It's a 2009 Yaris automatic diesel that needs the gearbox fluid replaced as the sump rubbed has corroded and when checked the fluid was minimal. So I'm hoping for some advice on where exactly on the gearbox can I find where the fluid goes into it? From research it's located at the side near the top but when I've looked there's a break plate attached to the gearbox which I've not seen on the diy repair videos.

Thanks for any advice.