The diagnostic mode also has speed in digital display. Before you start the car press and hold reset and units, start the car and let go of one of them first. I don't remember which one. As long as you are riding on stock rims and tires your digital speed should be almost right on. Than all you gotta do I adjust the speedo needle until you are almost right on. The same goes for engine rpm, since they are digital as well. for fuel and water temp, its best to make a small mark on your old guage face before removing the guage face, that way it'll make it easier for you to know where to put the needles at. It also works well if you have the engine warm and the fuel not full or nearly empty. Hope this helps.
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