I bought a replacement F1 relay from Eurospares for my GS as I had heard on the forums that it was good to repalce it as an 'insurance policy' for the F1 pump (i.e. it was relay which caused the damage to the pump if faulty).
When I finally found the location of the relay and replaced it (the new one was slightly smaller and had less pins). Reconnected battery and first off no priming noise when you opened the door. Turned the ignition and the starter motor wouldn't fire. Tried again - but still nothing.
Replaced the old relay and hey presto everything worked again as it should. I have sent an email to Eurospares to see whether they had sent me the wrong relay - still waiting for a response.
The above probably doesn't move the discussion on, but it highlights that the relays will differ from car to car and it is probably best to get a direct relacement relay (i.e. same part number) if you are going to change it...