I did one in my wife's car about 10 years ago. It worked great. They make a "kit" to do it. It has the tap and coil to do it. No drilling required. You put grease on the tap to catch all the shavings. Tap the bad threads then clean real good. The kit comes with some lock-tite to hold the heli-coil in. Then in goes the plug. Make sure you use some anti-seize on the plug threads. This was on a chevy 2.8L. I say don't pull the head and give it a try. Got another 50k on it before I sold it....It was still running........

- Daily Driver - 2004 Corolla
- Off Road - 1992 Pickup SR5 3.0L 4x4
- Fun - 2001 Camaro SS (320 RWHP/330 RWTQ)
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