To cut, strip, and crimp a wire, you can get away with using one multi-tool, but serious wiremen usually find specific tools they become accustomed to. The orange-handled tool shown above is a fancy wire stripper that holds the wire with one set of jaws, and pulls the insulation away with the other. The large red-handled tool is an MSD ratcheting crimper that has removable jaws for standard connectors, Weatherpack connectors, and spark plug wire ends. The smaller red-handled tool is a traditional crimper that's better for hard-to-reach areas. Keep standard electrical connectors around just in case you need to modify something, though American Autowire includes all of the connectors you should need for the kit.
Zip Ties/Side-Cutting Pliers
When it comes to zip ties, it pays to buy in bulk! A 1,000-count, 4-inch zip-tie back was $11 from the local electrical supply store. Side-cutting pliers are the best tool for cutting the tails off the zip ties aside from a zip-tie gun.
Wire sheathing is the key to cleaning up exposed wiring. We used this nylon material that expands as you push it together, like a Chinese finger trap. It grows to about double its taut dimension to allow you to easily push it along a wire and over connectors. On the small side there is sleeving meant to hold a wire as small as 3/32 inch that expands to about 1/4 inch. At the large side of the scale is the sleeving that at its smallest diameter is 1.5 inches but can hold up to a 3.5-inch bundle. There are different varieties of sleeving to accommodate heavy-duty or high-temperature conditions as needed. The two sizes most commonly used in the Mustang's harness are the 1/4- and 3/8-inch spools. They are very reasonably priced, so keeping this stuff in stock is a great idea.
*All prices are from the McMaster-Carr catalog