Sounds like a hell of a job to be doing in the driveway mate, I do not envy you. One thing to check whilst you have the tailshaft out would be the centre bearing. When we I had the diff done in the ute we found the centre bearing was seized to the tailshaft. I ended up finding a V8 ute tailshaft at a Commodore wreckers in Salisbury, it was out a stato that had just come in that day (ie different to the sedan as long wheel base). Point is my old tailshaft was cactus due to the centre bearing and even an engineering place I spoke with could not rule out destroying it whilst trying to remove the centre bearing. So cheap to replace whilst it is out if you can remove the centre bearing easily and will save you arse pain in the future
