In the middle of changing the coolant in my SLK320. Only drained from the radiator drain plug so far and I'm 2 to 3 quarts short of the system capacity. I'm guessing I better find and drain from the block drain plug too. I would prefer not to disturb any of the hoses if I don't have to, but I will disconnect the lower hose if I absolutely have to. Before I do that, can someone tell me exactly where the block drain plug is and what kind of a bolt it is? A photo would be fantastic. I found one reverse or external torx bolt on the passenger side (right) that might be a candidate, but I didn't want to mess with it until I was sure.