Like most other German cars, MB uses real copper wire for their plug wires. Theoretically it should give "zero" resistance.
For radio suppression and to elevate the idle firing voltages resistance is added at the ends of the wire and in the distributor rotor. The wire ends are usually 1000ohms but some of the earlier cars had 5000 ohms on the plug end. I think all the distributor ends are 1kohm. The sparkplug connectors say what their resistance is.
So for most cars a plug wire should be 2k ohms.
Bosch Master, ASE Master, L1
33 years MB technician