For curb inlets, we omit the offset since the contractor knows the face of the inlet must align with the face of curb.
Here's one to share: I had a road profile and the reviewing agency wanted to see the structures in the shoulder plotted on the road profile, so I showed with sta. offset. Fast forward>>> 35 years after the job was on the shelf, and another "engineer" modified the road profile to follow the offset drainage structures! Holy cow! So now they call me because my initials are on the plan.
One other option that you may be able to use is in creating an expression the subtracts 1/2 if the outer box dimension from the offset dimension and add that to a label style. This would cause you to have a couple of label styles.
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