Add a value to a dminesion in a notation

You can change the tolerance type to limit. then change the upper limit to .060.

Do you mean override a dimension's value?

If you click on the dimension in question you have options on the left, towards the bottom there's a checkbox in Primary Value, to "Override Value:", click that and you are able to input any value you want. Alternatively you could clear the text in Dimension Text just below Primary Value and you might get a warning about disabling tolerances, hit yes to that and type in any value or text you want to appear instead of the true dimension.

If I'm understanding you, you want a dimension to show up in a note. Though, I'm not sure why you'd want to do this in a sketch.

Create your dimension.  Create an annotation note.  With the note active, simple click on the dimension.  It's value will be added to your note.

Just open a new sketch in the part, anywhere. Draw a line and dimension it. Assign an equation to that new dimension = "A"-Dim +.060, where "A"-Dim is the nominal dimension.

Hide the new sketch. Link the new dimension to a Global Variable.

In the drawing refer the global variable or the new dimension inside the note.

Another work around idea;  Turn on tolerance type to limit (as someone else suggested earlier) and put in the lower limit "+0.06" put your higher limit in.... any good?