What kind of electrical niggles? Any particular reason why you suspect a fault routing to 0V?
Personal opinion: I would suggest that even if you do find corrosion at such points, the corrosion is just as likely to be protecting a decent connection beneath. Besides, they are generally located at positions that are well protected from the elements.
If you haven't already, do the basics: continuity checks to the equipment in question, measure the V+ present. Let us know if you find anything interesting.
try cleaning up the batery terminals, pour BOILING water over them, after remocing the conenctors & over the connectors too.... then apply vaseline over the tops of them to seal them for future corrosion.
* gearbox x 1
* on each valance, jsut under head lights x 2 [ ...13mm headed bolts ]
* ecu frame [ t25 headed bolt ]
* on the head near throttle body [ TS ] or front head [ V6 ] ...13mm headed nuts