Very good point, hadn't thought of corrosion. Be careful fitting a higher rated fuse though, as the more current a cable draws the hotter it gets. Best solution is a multi meter evrery time.
Have you printed off the wiing diagram and traced through all the wires from the fuse that's blowing? Would help to eliminate all the stuff which isn't causing the problem...
_________________
MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball