Hy Colorado51three-quarter, most clutch discs will only fit on one way, the cushioning springs on the disc will not allow that side to sit against flywheel, it will interfere with the flywheel bolts, most new discs are marked flywheel side. The pilot bearing has a radiased side, that side faces the transmission, it makes it easier for the input shaft to find its way into it. Cleaning the flywheel and pressure plate can be done with any good brake cleaner. As to centering the disc, you can do a good job just by making sure it is in the same position relative to the pressure plate all the way around. Now a note of caution, I would want to figure out what caused that damage to the disc, before I put it back in and applied power to it, chances are something locked somewhere in the driveline to cause that damage, hope that helps.
