The starter on a 190D is located on the driver's side just behind the engine on the top-left just between the engine and the firewall. To get the best look at it, you have to remove the air filter and the air filter compartment. It is the hardest job of all to replace. iT'S A 9.5 on a 10 point scale. In most cases it takes two people because the two bolts that secures it to the engine are out of the line of sight and it is difficult to align your tools. It also has to come out through the above opening and it is more difficult than giving birth to an oversized baby and I am a guy so I should know (ô¿ô). I replace mine's with the help of my dear patient brother and it took us approximately 3.5 hours. He is a professional mechanic with all kinds of tools.