Mercedes: Twin Fuel Pump Replacement, fuel pumps, fuel hose

Question
I have a 1986 Mercedes 560SL with twin, in-line fuel pumps. If one goes bad should I replace both pumps at the same time or just the bad one? Anything I should be careful about when replacing a fuel pump myself?

Answer
That's a tough call. Depends on what happened to the one that is bad. Is the old one working OK. How did  you determine which pumps is not working.
Disconnect the battery ground wire. You will need to clamp the rubber fuel hose to keep fuel from running out. Use new line seals. The old ones will not work.
Be sure and use the proper wrenches, so as to not twist the line. Replace the filter as well. Be sure all connections, including electrical are tight on install.
Let us know how it comes out.