Just a note to those contemplating an oil cooler addition. I got mine nearly done and ran into a problem with the adapter. I purchased the Derale Thermostatic Model D25732. The problem is that the adapter is designed for 2 3/4" gaskets and the stock filter gasket is 2 1/2" and too small to seal properly and it leaks. That adapter will "only" accomodate a PH3950 or cross reference filters that are too big in diameter to mount on the adapter as it hits the engine case above. Had to go back and ordered the Low Profile D25772 which takes filter gaskets 2 1/2" and 2 3/4". No thermostat.