Couriers were rust prone turds with fuel pump failures, timing chain rub strip problems and often warped heads and blown head gaskets. They don't deserve to park near a Ranger,much less be called Rangers.
We quickly devised a fast head gasket test when we sold those things. (1) open the hood- they tilt forward, (2) remove radiator cap, (3) get in, roll up the window, and start the engine. If the coolant erupts in a geyser and covers the windshield, the head gasket is blown. "Roll up the window" was added after the first time when coolant came in the window.