I have an European differential cooler setup, came stock on the Z31s, that I am converting to use AN fittings.
This is how the setup works, pretty simple really.
Diff cover: same as the stock z31 LSD cover but it has been drilled behind the breather for a pickup tube with filter. Both plugs have been replaced with sensors for the thermostatic switch that operates the pump.
Housing: same as the stock long nose z31 in the USA with one caviat, the top of the housing directly above the carrier has been tapped for the return line.
Pump: mounts to the frame uses banjo feeds. Pumps about a gallon a minute if I remember correctly
Cooler: long with only a few rows, mounts to the frame 2 nipples feeding the side
I'm never satisfied with stock so I am replacing the cooler and the nipple/hose design with a nice AN setup with a slightly bigger cooler core. When I eyeballed the stock hoses they looked to be 5/16 maybe 3/8s, that would translate to a -5 or-6 respectably. Most aftermarket setups look to use -8 so that worries me a bit. Besides that I need to locate a banjo to AN adapter that will work with the stock pump or replace the part. The last problem is welding a fitting to the diff housing and cover for the supply and return.
Mike