The BEST fix is a new case.

The second best fix is to pull the rear case and have a machine shop fix it. Yes, Heli-Coil does make repair kits that big and metric, but...they don't actually stock them. But, for about $4 each, you can get the insert. But, you have to buy about a hundred of them.

I had a machinist mill out the threaded area and install a press fit steel insert that was threaded for a new plug. But, it also cost me about $150 bucks. I had my reasons and the work was so beautiful that it would make you cry.

Barring that, the rubber plug is your next best bet, followed by a stick wittled into a point and jammed in there.

I would stay away from the self tapping plug. The case is aluminum, and Al does not take self tapping things installed and removed again and again and again, very well.

Good Luck,
Michael

PS, this should all be followed up by laying off the anabolic steroids and having tattooed on the back of your hand, "Righty Tighty, Lefty Loosey". <img src="/forums/images/graemlins/smile.gif" alt="" />