I helicoiled mine.........
Tear off a very long strip off cotton cloth and soak in oil, feed in through the sump plug hole, making sure you push it away from the hole a little and mark where you leave the end.......
Re tap the thread using the helicoil tap, remove any sharp edges inside the thread, then hook the oily rag strip out, pulling it out gently, it will drag out all the swarf with it.......
Measure depth of threaded portion and pick the correct insert....
Now do one of 2 things, either put in another piece of rag or get a strong magnet (inserts are steel) for when you break off the tang....
Fit the insert (these are tricky, take your time, if its poo do it again, they are fairly easy to remove....make sure the wire insert is half a thread under flush......break off the tang
Fit sump plug.........