Yup, I'll drill out in stages and try to retap. I might give the extractor a quick go at the bigger diameter as its unlikely to break. Will update here once I'm done.
All I wanted to do was change the bloody oil...
Yeah its the way to go bud, I had to do this on mine. Bit of a pain in the bum when doing it back up because of access (mine has a bolt front and back as previous owner was obviously a bit of a meat head), the rear one is obviously a pain, but after a couple of services you get the knack!
When I was down getting some parts from the local garage they had a td5 sitting on the deck, he said i could have the housing for free, but couldn't be arsed in the end!!