No diagrams here in WikiAnswers, but the 2 "Related Questions" below will provide lots of written information and instructions for cylinder numbering, coil numbering and getting / keeping the engine firing order straight.
The "How do you know which wire...?" question is oriented to folks just learning about cars, and the other is "just the facts".
For a 1999 Ford F-150 with a 4.2-liter V6 engine, the spark plug wiring follows a specific firing order of 1-4-2-5-3-6. The cylinder numbering starts from the front of the engine, with cylinder 1 on the driver's side. The spark plug wires should be connected to the ignition coil in the correct order: cylinder 1 to coil terminal 1, cylinder 4 to terminal 2, cylinder 2 to terminal 3, and so on. Always ensure to consult a service manual or wiring diagram for precise routing and connections.
Right above the thermostat housing..
cylinder location is stamped on the intake right above the cylinder. the firing order is also stamped on the intake manifold
If you look under the hood on the passenger side near the belt, there is a diagram near the belt location.
axon terminal
The spark plug diagram for a 1988 Volvo 240DL typically follows the firing order of 1-3-4-2, with the cylinder arrangement as follows: Cylinder 1 is at the front (near the timing belt), followed by Cylinder 3, then Cylinder 4, and finally Cylinder 2 at the rear. The spark plug wires should be connected accordingly: Cylinder 1 to the first terminal, Cylinder 3 to the second, Cylinder 4 to the third, and Cylinder 2 to the fourth. It's always best to consult a repair manual for precise diagrams and specifications.
axon terminal
firewall 3 - 6 2 - 5 1 - 4 front
Diagram can be found in the proper Haynes manual, available at most auto parts stores. Coil paks may also be numbered for easy identification.
A battery terminal diagram illustrates the connections and polarity of the positive and negative terminals on a battery, showing how they are connected to the electrical system of a vehicle or device.
ML 430 cylinder diagram
firewall 4 - 8 3 - 7 2 - 6 1 - 5 front