Oil & Fuel Hydraulic fill location

[Mark in BC]

I have a 1964 Massey 65 gas. I need to add hydraulic fluid for internals and 3 pt hitch. Where is the fill port?
A pic of the location would be nice if someone could post.
I thought I had found it on top of the trans casing on the left side, beside the hydraulic levers, but when I loosened off the plug, a yellow fluid came out. And do you check fluid level with engine running or not and with hitch raised or lowered.
Thanks

 

[AllDodge]

Have a read at the below link but Big Dean said

MF65 has a common reservoir for the Transmission, Hydraulics and Differential. All three are filled at the big plug just to the left of the main transmission shift lever. They all three check with the dipstick in the access plate on the right side of the rear center housing. They hold 8 gallons of oil when completely drained. To get all of the oil out you have to pull both drain plugs.

http://www.ssbtractor.com/wwwboard/view_all.cgi?bd=massey&msg=4896