Hey, that's really awesome that you're reading and studying and all that........ it is really a great help in learning to install better.
As you've surely learned, those wiring sheets are usually very vague, and sometimes flat-out incorrect.
---Kick panel wires: In the kick panel, you'll generally find two things......the wires coming into the car from the door.......and the wires running from the front of the car, to the back.
In general, you'll find locks in the door harness.....and parking lights, brake, and trunkpin in the harness that runs to the rear.
---Another trick for finding lock wires: Operate the power locks, and listen for the factory relays clicking somewhere behind the dash. At the very worst, you can often locate the relays themselves, and get the lock wires there.
---Coil packs:
Most newer cars don't have a distributor anymore. Rather, there is an individual coil atop each spark plug.
Likewise, few cars use carburetors, or throttle-body fuel injection.......usually there are individual fuel injectors atop each engine cylinder, usually somewhat near the spark plugs.
If it's a six-cylinder car, for example, and you see six identical items neatly arranged atop the engine......they're most likely to be the injectors or coils.
Often, although not always, you can use your choice of either an injector or a coil for tach.......they both put out pulsations when the engine is running, which is what the remote starter is looking for.
Some cars maybe 5-10 years old will have what's basically an electronic distributor.......a box with 4, 6, or 8 spark plug wires coming from it......usually you can find your tach wire there.
Also, there are many, many cars where the tach wire is easily available inside, the but the tech sheets don't tell you.........if you get a particular car, ask us and maybe we can help.
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The most important thing, is to try to think for yourself how the car is constructed. Some newer cars, particularly GM models, will have a lot of computer modules that communicate with each other via databus signal..........but for a regular, tradional car, you can start with the following assumptions:
--The power lock wires probably come into the car through the door harness.
--The parking lights, brake wire, and trunk trigger will probably be in the harness low in the kick panel, running to the rear of the car.
--The domelight can often be used as a door trigger.....all of the wiring going to the roof of the car MUST be running up one of the roof pillars.....often the driver's-side A-pillar.
--Parking lights are also found in plugs at the fusebox, and sometimes the brake wire as well.
--The horn wire is usually coming from the steering column. If you can't figure out which wires go to the car's airbag, test carefully.