BuckCrouch

My dad has given me his Ford tractor, which he always referred to as a 600 (it replaced his old 8N, to my mother's tears). My dad has problems with his memory at age 87, so it doesn't do much good to ask him any questions about the tractor. The serial number appears to be 631 10305. This confuses me as it is four speed with the implement lift AND a PTO. How can I find out what it really is? Or does it really matter?

The second problem I have is that the implement lift does not work. The reservoir is full to the mark and the pump is primed as I opened the Allen plug on pump and when I turned over the engine I got oil out. I do have a hydraulic pressure gauge and I'm assuming that the pipe plug on the lower left side of the oil reservoir is where I want to mount the gauge, is my assumption correct? If so, what pressure should I read? Any other ideas?