Barndoor,
The aluminum block engines don't use torque to yield(stretch)bolts.Look at the torque specs. The bolts that will break if stretched too many times are torqued at a 90 deg. angle of rotation.Your biggest concern is if the threads pull out of the block.At some point MB switched to a special alloy bolt to prevent this.If your bolts are a bright metal color, you're fine.
Good luck,
Peter

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