How to repair damaged O2 sensor threads?
 

Was replacing the driver side O2 sensor on the exhaust manifold and of course, threads were ruined and called up. Tried to run a thread chaser through it and it actually cross threaded and took out like 4-5 rows of thread, talk about amateur hour omfg. so now I'm pulling the manifold now since nothing left in can do.

Anyone try to install helicoils or any other kits for new threads? Are they any good?

I believe a Time-Sert may be the better option to prevent you from having any issues after repair. A helcoil should work but is not as robust or permanent in my experience