you know what your on about. surely thats not all you did as an auto elec app?
i had the problem of the instrument panel lights wouldnt work, i tried for 2 days to find the problem, my old man had a look, the guy from next door, and the guy from across the road who knows about as much as superjamie it would seem and none of us could find the problem.
gave up and took it ot an auto elec and it turned out to be a dirty fuse box. FFS. morel, check the easy things befor you go looking for hard stuff.