Having suffered problems with my 940 fuel system, I have replaced the in tank pump with replacement pump from a BMW 318 the pump is longer and has a filter system which allows it to fit, the lamp requires adjustment as does the electrical fitting change from bolt on to push on.CHECK the rubber concertina hose for leaks or fractures, I had to replace mine with the flexy hose from the BMW cut long and fitted with a large diameter coil formed to absorb vibration. The only explanation for the fuel smell would be from a split fuel line before the injector rail.

Before removing any of the previously mentioned, check the pumps turn on when the key is turn on, these will activate for three to four seconds until pressure builds up, if this checks out, you will find the fuel level sender unit on the pickup unit with the fuel pump. It is possible that this problem has been attacked by a previous owner and the access cover in the floor has not been screwed down properly allowing fumes to enter the cabin.
Chris Boyce