Need help on changing hydro oil on 3400 pumps.

I have the new ferris stander with 3400 transaxle pumps. Getting to the filters was a task in itself but I can't get to the vent port to bleed the air. They are located on the top of the pump conveniently blocked by just about everything. I have to hunt for a special hex wrench that can bend around and up to get to this thing. Why they make it like that is beyond me.

Anyway, is there another way to bleed the air out of the system to accept the new oil??
Or is there a tool that someone...

Need help on changing hydro oil on 3400 pumps.