Nut size on the Speedometer Cable end?

[mrdrnac]

Quick question, can someone tell me the wrench size needed for the nut on the speedometer cable going into the speedometer? The PO torqued it down apparently, I can't get it lose with my hand, and it will be a job to get a wrench to it behind the dash, so getting the right size to it would help! Thanks in advance

 

[mrdrnac]

FYI, it is a 3/4" wrench size, in case anyone else ever needs it, finally got it! Now to lube the cable and replace (Hand tighten this time. %)