This may be a plubming question but would be better in the caravan/motorhome section as more people will relate to your problem.
The way I see it it should be screwed to the work top from above. check around the tap if there are any trim caps covering the screws. If screwed down there should be enough slack on the pipe/s to lift tap assembly up to remove the jubilee clips and micro swithc wires.
Bob, June 2009