Hey, I have putin the 500E rear sway bar in a 300E, no problems, make sure you get the bushings too, and replace the rear sway bar links at the same time. The 500E bar last summer listed for 212 dollars. so its kinda expensive, but it tightens up the car so much, but make sure you do the front one then the rear one, or both at the same time otherwise you will have some steering problems. I think it is called oversteer, dave would know.

__________________
Current Stable:
1994 S500 v140, 210k miles, white with grey.

Former Mercedes in the Stable:
1983 300CD Turbo diesel 515k mi sold (rumor has it, that it has 750k miles on it now)
1984 300CD Turbo Diesel 150 k mi sold
1982 300D Turbo Diesel 225 sold
1987 300D Turbo Diesel 255k mi sold
1988 300 CE AMG Hammer 15k mi sold
1986 "300E" Amg Hammer 88k mi sold (it was really a 200, not even an E (124.020)
1992 500E 156k mi sold
etc.