$110 to change donuts?
Starfighter.. try this:
Go to your local MB dealer and get the real donuts with the middle section - this will keep the muffler from bouncing up and down, which is why the o-ring ones can come loose (all that play in them)
Pull out a regular floor jack, roll it under the muffler, put a board in between, jack up the muffler and you should be able to change them with ease.
No need to jack up the car.
2003 S500 Black/Charcoal
1990 560SEL 61k Arctic White/Grey
1988 420SEL Black/Palomino Sold @ 85k
1987 420SEL Midnight Blue/Grey
1986 420SEL Diamond Blue/Grey
1983 380SEL Champagne/Palomino