Next, it is time to treat the plastic areas. This includes the center console, the clear plastic covering the gauges, and around the vents. Your best bet in keeping plastic clean, and in good condition is to use a good plastic polish/cleaner. 3M makes a great Polish and Cleaner product, as well as Plexus. Apply the product just like you would car polish, put a small amount on a towel or cotton swab and work it lightly into the plastic until it buffs out. Wipe off any access with a towel. For areas like the clear plastic in front of the gauges, you want to only use a good plastic polish.
The use of other cleaners or solvents may scratch the plastic leaving a cloudy haze and making it hard to read the gauges. When polishing this area, work only in a diagonal up and down motion, no circles. A scratch is most visible at a 90-degree angle, in a diagonal fashion, any scratches will be barely visible when driving.
The polish will leave all of the plastic looking rich and shiny again.
Plastic polish can also be used to remove scuff-marks in plastic and vinyl areas. Common places where this works well, is around the plastic shield over the steering wheel, the front kick panels, and the lower portions of doors. The plastic polish should remove some of the scuffing, and reduce the visibility of it. While some scuffing is to extreme to remove all of, it can certainly be helped.
Finally, all glass should be cleaned and removed of oils. A great technique being used by detailers for years is newsprint. That's right, your normal every day black and white newspaper. The ink in newspaper, when used with a light lubricant acts as a fine polish. This polish lightly removes weather damage, and embedded dirt, which then clings to the paper itself providing a great cleaning action. Using a light glass cleaner such as diluted Windex and newspaper does wonders. Make sure you never use this technique on the rear window, as it has thin wires, which are use to defrost and any abrasives from the ink could damage them.
Now the inside of your car should be looking great. The vinyl should be clean, and protected. The plastic should have depth, and its original color, and the carpets should be spotless. The only thing now is to wait for the next person who gets in your car to ask. "Wait, how old is this car?"
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Much thanks to StyleTeg for writing this up!!
Due to a glitch in the forum, this thread will be in Exterior for awhile.