I have a 1978 450 SL, Is it absolutily necessary to remove the distributor in order to replace the water pump, or does it only make it easier?

On my 560sl, the hold down bolt had to be taken out to clear one of the water pump bolts. The dist. did not have to be removed.

I'd try taking the bolt and spacer out first to see if the water pump bolt is revealed.

J. Boggs