Hi mate, yes a new tailshaft/driveshaft. I had the same problem with the previous driveshaft which is why I've replaced it with new good quality uni's. I must be close because what ever I did has affected the vibration (worse). Actually to the point where I am afraid to sit at that speed for fear of throwing the driveshaft.
As I have disturbed the rear shock mount I will check the pinion angles again just to make sure nothing has changed. Juts need to be away from it for a few days.