Without getting into details, ive seen videos of people drilling out and re-taping these. Drilling to 17/64 and turning a M8 1.25 tap, does this work? I would expect running the tap will destroy the old threads instead of hoping the tap will more or less following the existing threads. Has anyone does this with good results? I also have a threaded insert i could use drilling up to 21/64 and winding in the insert. Does anyone have an recommendations? Thanks.

 

I've seen videos where people weld nuts to the end of the studs, saturate the stud and nut with pb blaster while their still hot, and twist them out

 

The stud im dealing with is the front bottom stud passenger side, Ive had a welder look at it and he suggested that there is not enough clearance for a welding gun.

 

He's not wrong. The driver side is easier. Removing the wheel and strut usually leaves enough room to get in there. Imo, the easiest way to replace the passenger side exhaust manifold would be to pull the motor. Or loosen the motor mount on that side and use a jack to lift the right side of the motor up to reach the studs. But even then it's not as easy as the drivers side