Not to worry, you need a longer bolt. You can order several increasingly longer ones on line with little trouble.
There is extra threaded hole depth left in the hole that had the top part strip out. There are lots of references on line on how to turn a bolt into a one time tap, so do that to your longest bolt.
Once you tap down to find the bottom of the existing drilled hole and have tapped as deep as you can, count the turns of engagement. If you have four turns or more you can use the hole "as is" without drilling for additional depth, just go with a very mild tightening of the bolt.
Spec on those things is 70 to 100 inch pounds (you can read that as 5 to 8 foot pounds, 5 pounds being moderate finger pressure) and YOU DON'T HAVE TO TIGHTEN THAT MUCH TO GET IT TO SEAL. Your goal is to tighten it just enough to seal the oil leak, then quit. Since it is a no loss proposition, you can sneak up on it from the bottom end gradually.
Notice this method requires no disassembly and no big labor charges, so of course the dealerships won't tell you about it.
But we will .....
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Next, read up on the head plug leak -- go to the index at the top of TECH SECTION to find it. Odds are some of you leak may be coming from this, but since you stripped the threads on the long bolt you have to fix it anyway.