Starter motor mounting stud nut size?

Hi all. First post here as a newbie Series III owner. I've had "Giles" for a couple months and it's been a blast. I've gotten very good at hand cranking it since my starter packed up. Got the telltale "click", swapped the solenoid to no avail so ordered the high-torque replacement starter motor from our hosts at RN and plan to put it in this week. Does anyone know the nut size for the mounting studs for the starter? I'd like to make sure I've got the right size before getting into the job. Also, any other tips are appreciated. I did buy a new solenoid to starter cable and figure on swapping that out at the same time.

Thanks in advance!

Never mind, I went out and put a wrench on the top nut. 9/16" for anyone's future reference.