Beyond the plug type, the firing order is crucial for proper engine operation. For the 3.0L V6 in the 2000 Ranger, the firing order is 1-5-3-6-2-4. This refers to the cylinder number in the order the spark plugs fire. Make sure you replace the plugs and wire them in this exact order. A mis-wired plug can lead to misfires and damage to your engine.