I changed the front flex disk on my 88 300E just recently. It was a fairly easy job. Raise the car and put it on reliable and very stable jack stands, keep in mind that you are under that car and you do not want it to fall on you. You will have to remove the six bolts that attach it to the transmission and drive shaft, then using a very large screwdriver as a pry bar pop the bushings in the flexdisk out of the counterbores in the drive shaft and the transmission. You should be able to slide the driveshaft back about 2" to the rear. I did not drop the center of the drive shaft but instead I put a jack under the transmission removed the transmission mount and carefully lowered the back of the transmission (about 3/4") until the flex disk fell out on the floor. do not lower it too far as you may damage some things at the back of the engine that you are not watching. I then put the new flexdisk in, slid the driveshaft forward and using the new hardware
supplied with it reassembled it then tightened everything up. Keep in mind the flex disc IS directional. The side with the numbers on it goes toward the REAR of the car. Once everything is torqued properly put the transmission mount back on raise the transmission and tighten that up, you're done. I got my parts at the Parts Shop in a matter of two or three days and was very pleased with the price and quality.
88 300E 225K Sold
2000 C230K Totaled @103K
2003 ML320 140K Granddaughters Limo
2009 E350 4Matic Sport 37K Sold
2011 ML350 44K