I went to look at a 76 450SL today that the owner is selling pretty cheap. Owner says the car started running rough recently , it has 122k miles,on it, and he doesn't want to put any effort or money into finding out why. That always throws up a red flag for me but I figured I'd ask the forum if there are some common things I can look for that would cause this. The car runs but you can hear it is not running smoothly and if I push on the accelerator it revs up very slowly and the miss does not go away. If I had to guess I'd say at least 4 of the 8 cylinders aren't operating. The car is pretty clean otherwise so I'd like to pick it up it this can be fixed for a reasonable price. Any ideas? Thanks