I think I'm having issues with my Regulator/Rectifier, my bike keeps blowing up headlight bulbs, I took my Regulator/Rectifier out and the pins where covered in green corrosion, after sanding that off and cleaning them I don't wanna put it back in yet before I make sure it's functional. Does anyone know how I should test it? My user manual just says to check the batery voltage whilst it charged from the running engine. 

Yep that's the way, multimeter across the pos/neg then run the bike at about 2K and it should read 14.5 volts, if it's more then the thing is buggered. Far as I know it's not possible to repair them. Heat is the enemy of these things, check to see if you get a reasonable airflow when riding, if not then reposition it so it get's lots of cool air.