I just used a Big-sert by Time-sert to replace a messed up helicoil in my manifold
++ BIG-SERT Oversized thread repair kits ++ thread repair kits for oversized holes, previously repaired threads oversized holes - https://www.timesert.com/html/bigsert.html
++ BIG-SERT Oversized thread repair kits ++ thread repair kits for oversized holes, previously repaired threads oversized holes - https://www.timesert.com/html/bigsert.html