High pressure auxiliary line

[olman]

I have a New Holland l223 and a Turbo Saw that I would like to hook up. One hose on the saw says "high pressure side. I have three auxiliary ports. The center and smaller I know to be a drain back line.. Is the inside or the outside line the high pressure side? This is a low flow machine. I have the owners manual as a computer down load and it doesn't tell me much. Thanks. Pete

 

[Tazza]

Generally, for normal operation, the female connector on the machine is the one that gives the pressure, but if it's backwards, just swap fittings on the attachment.
You're right, the small one is case drain.