Yep...first signs of my reg (actually the wiring and connector block) going was the needle jumping around and then the engine going lumpy, until it evetually wouldn't run.
Check the connector block where two yellow wires go into it, behing the battery tray. Disconnect the connector and take a look inside...is it looking a little corroded or going black???!
[Edited on 21-7-2005 by Harv748]