I drilled and welded a threaded boss in the bottom of the
oil cooler to accept an allen plug, also drilled a 3/4 inch hole in the body directly under the cooler, this drains most all the
oil. a little extra effort but, I wanted it.
A hydraulic guru told me, for every 90 degree fitting you install, it's like adding 3 feet of hose. Not sure if this applies to automobile
oil lines?.