In general Heli-Coil is the best idea for thread repair/replacement in a threaded hole, gets you back to standard size and the hole is now stronger than it ever was.
Some odd situations will benefit from a different repair, but if a Heli-Coil will work consider that first.

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-