I recently replaced the water pump on a 1986 420SEL and the notch in the harmonic balancer was clearly designed for another purpose. I had to take the balancer off to complete the job. Took the distributor out too - not as bad as it sounds. The radiator stayed in; replaced every belt while I had everything apart. Have you done this project yet?

__________________
Simon Shearer

1986 420SEL

2000 Porsche 911 Millenium Edition Carrera 4
2010 Lexus RX 350
2002 Kia Rio
2002 Hyundai Accent