The most important thing before you even unbox your plug wires is to be able to correctly identify your engine's firing order and cylinder numbering system. There are no do-over's once you start cutting wires and crimping terminals, so it is a necessity to get it right the first time. On race engines, plug wires and distributors are constantly being removed. Save yourself the chance of making a mistake and go ahead and number all eight plugs on your distributor. It may look a little amateurish, but it is still a lot better than trying to start a race with a bad miss because you've gotten two wires crossed.