One way you can replace the stripped stud in manifold
Since you appear to have access to stripped out stud hole I would remove stud from manifold and get a bolt long enough to go through from the top.
Either use a smaller diameter bolt, washer and nut or drill out hole in manifold slightly so you can drop in same diamter bolt which is 8mm that is long enough to add washer and nut under exhaust pipe flange.
Since you appear to have access to stripped out stud hole I would remove stud from manifold and get a bolt long enough to go through from the top.
Either use a smaller diameter bolt, washer and nut or drill out hole in manifold slightly so you can drop in same diamter bolt which is 8mm that is long enough to add washer and nut under exhaust pipe flange.