My routing is the filter, then an oil thermostat, then a B&M supercooler w/fan. Fan switch is 170 on 140 off. Oil thermo keeps you from overcooling oil and hurting bearings. You want 180-210F. Fan is not required if you put it right in front of the radiator. I attach my cooler to the grill in my 56, which about a foot in front of rad, so fan is needed.

"The first rule of overkill: You can never have too much overkill."
"Overkill is underrated."