You may have a short somewhere as it shouldn't blow the fuse and that obviously means that it's drawing too much current from somewhere. But have a look at your fuel relay, it should be the big one at the top left of the fusebox. I think it sits in position 2, but not 100% certain.
Do a serch in this mk1 section for fuel relay as I seem to recall that you can bypass the fuel relay to check where your problem lies, but this is not a long term solution as it's just a trouble shooting exercise.
