@cme469 - on the driver side the two outer bolts are indeed missing. First I thought - based on the remark by my mechanic - they sheared off. Then I checked the holes (with the manifolds in place) only to see that there are, apparently, no remnants of them in the head (holes considerably deeper than the thickness of the exhaust manifold at this spot). Preliminarily, I came to the conclusion that they were not installed after a previous fix. However, the spacers are there on the second outer most bolts. This would corroborate the statement that the outer ones weren’t installed by the factory at all. The passenger side one has got 6 bolts installed. But this was obviously removed once since weld seams of former cracks are visible. Amk also mentioned that I could buy a second set or 4 individual bolts in case I want to have a bolt for every hole.