guys, thanks for all your help..great information !!

This last weekend changed out my front shocks with Bilsteins on my 1999 ML430. Pretty easy job. I found it easier to totally remove the fender liners in order to get to the top nut on the shocks. BTW, the Bilsteins have a better design than the Arvins that were removed. The top of the piston on the Bilstein takes an allen wrench that prevents the piston from turning while you tighen the hex nut on the shock.

Planning on changing out the rears and replacing brake pads this next weekend.