Where is this speed actuator loacted? Is it the cylindrical thing about 5 inches long underneath the intake manifold. If it is this, then should it be nonadjustable (my case) or should it have a black screw to adjust the idle speed? Someone recommended using the adjustable type to lower the idle speed. Others say the 2.3-16 came with nonadjustable type (ECU controls idle). Which is correct?

Has ayone had experience dealing with the plugs that convert leaded into unleaded?