Meritor Transmission fill plug/fluid check plug??

I have a 10 speed meritor transmission in a 2000 Volvo vnm and I can’t seem to find the fill plug or dont know exactly where to check the tranny fluid level. I’ve found the breather and the drain plug but not the other one. I’m wondering if anybody would have any input on that.

 

Thank you so much I think I found it now. It looks like it’s a squared nut and might need to use some sort of pipe wrench to take it off.I appreciate the help!

 

i really do appreciate it man, I was looking for a differential type nut for the plug this whole time so I felt clueless but I’ll get to it right now.