Ran into a snag - because I started drilling and threading for 3/8"NPT fittings and then changed my mind and went 1/2"NPT so I could run -10AN hose for the oil cooler, the fittings were now too close together to assemble. This would not do.
So I ran a plug in through one, and drilled (at an angle) and tapped the end of the oil cooler block to relocate the fitting.
Also ported the mother-loving mess inside to make it flow decent.
Pretty sure it's not a thermostatic valve - looks more like a pressure relief valve inside.
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