We begin the internal inspection by removing the valve covers to get at the rocker shafts. Fairly clean in here, but the engine is obviously no virgin, at least up top. Indicators of previous abuse include silicone on the gaskets and near the front rocker-shaft hold-down bolt, which was drilled and tapped from the factory's 5/16-inch fastener all the way to 7/16 inch-ouch! Also notice the incorrectly matched pairs of rockers: the right and left rockers mixed up on cylinder #1, two lefts on cylinder #3, and two rights on cylinder #7. Finding this kind of ham-fistedness means trouble. From here on in everything goes under the microscope.