Periodically the temp and fuel gauges start flipping up and down. I have tested the earths and the gauges themselves and all is OK. I suspect it is some sort of problem with the voltage regulator - question is does a 1992 200Tdi 90 defender have a voltage regulator and if so where is the little critter?

Haynes manual talks about a voltage resistor and printed circuit board (chapter 3) but then refers the reader to chapter 13. Annoyingly I cannot find any info in chapter 13!
cheers

Alternator takes care of these things... The back of your alternator looking frazzled at all?