Several errors in this video. Using a sandblaster is not recommended for aviation plugs, the blast media may wind up in your engine. If you use a crows foot as he mentioned , you may overtorque if it is not positioned correctly, 90 degrees to the wrench. I wouldn’t use a wire wheel on a plug either, it removes plating. Don’t use a Thread-chaser as you may pull out or damage the helicoil, and then its cylinder removal time! And as far as putting the plugs in the same hole, they should be rotated for mag polarity, on a 4 cylinder engine diagonally opposite. Its more complicated on a 6 cylinder. So yeah, get the manual so you don’t do some expensive damage to your engine! Check out publications from the plug manufacturers! TC A &P/ IA