bob.......you ask......."it has dip stick under seat on rt. side,says level here when cylinders extended??"........"thatza 1-size fittz-all hydro-tranny dipstick".......the cylinders are built into BIG HEAVY WIDE disc cultivators for hydraulic operate rubber tired roadwheels. The state gitts kinda upset when your disc leaves scratches on their nice asphalt. There is some additional plumbing that hazzta be made on yer tractor hydraulics for them hydraulic road wheels to operate. Same with BIG plows. Not all discs are 3-point liftable.
Tip: while the 8N's originally used 5-gals of 90wt hydro-tranny oil, Ford/New-Holland now recommends specs: M2C-134D hydro-tranny oil (abt 60wt) Drain yer square diffy plug first 'cuz it peeeees with some degree of accuracy. Then drain the 3" tranny plug, and finally drain the 3" hydro-plate plug. The corner test port is NOT a drain.
Ittza good thing to keep yer hydro-tranny oil under-filled 'cuz overfilled hydro-tranny oil will splash out yer rear axle bearing seals and grease yer brakes. Not Good, eh? The tranny front seal will also leak and grease yer clutch. Not Good, either?
To eazily set yer 5-gals of hydro-tranny oil, remove the bottom 6-o'clock bolt from yer six-inch roundy dipstick plate behind yer right heel and letter drain down the outside of the tranny. Simple, eh? ........the greasy Dell