I am getting ready to fab up mounts for a remote oil cooler that will be in line with a remote oil filter as well with a thermostatic cooler bypass. Here is my question - should I mount the cooler with the inlet and outlet pointed down so that all the oil will drain through the filter adapter (downhill from the cooler) when I change oil OR should I mount it inlet and outlet up to prevent it from draining when I shut off the engine and then taking a longer time to build oil pressure when I start it up. The cleanest line routing is to have the inlets on the bottom andf I'm not sure how long it would take to fill the cooler after startup. The cooler is roughly 8" x 11", Mocal I believe.

I plan to plumb the oil pump outlet to the filter first then to the cooler and bach to the engine. The thermostat will be between the filter and cooler and in the cooler return to the engine.

Any ideas?