Rich,
I was looking at the very same thing for my A4, because I want to change the fuel system when I do the turbo upgrade (I'm figuring bigger injectors will be better serviced with a higher flowing pump, adjustable FPR etc.), so I looked at the good ol' Haynes manual...
Procedure seems pretty straight forward but they do say you'll need a special tool to get off a locking ring that holds the pump in the fuel tank. Or, as thay also suggest, it may be possible with two screwdrivers crossed over, whatever that means!
I'm sure there'll be some way of getting it out, only way to tell is to have a go I reckon. I don't think it's a big job.
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