I have not done it yet on the ML
I have done it on several previous cars and motorcycles.

Just replace them one at a time so they don't get mixed up.

I just ordered a Service Book yesterday that claims to have tune up information on the ML320.

check back with me in a week. It should be here. Maybe its trickier than I imagine.
sdanville@grar.com

__________________
Steve Danville
what i did myself.
CPS
rear shocks
MAS x 3.
SparkPlugs (twice)
Fuel pump & Filter
Window switch
replaced both failed horns with Honda horns.
Cleaned ERG Tube
Oil changes
Oil consumption Fix
Brake Pads
A/C Recharge
Anti-Freeze change X 2.
Front Shocks. Monroe. $90
Mercedes Warrenty Work:
Harmonic balancer,power steering clamp. Cat converters.Drive Shaft Bearing.s
Replaced Outer Lower Tie Rods and front lower ball joints at 156,000 miles