Need help with dimension to center it and adjust leader line?

See the associated image; what I have is on the left, what I want is on the right.

I've looked in SW Help and online but can't figure out how to:

a) center the 11.83. It keeps flipping to the left/right of the vertical leader.

b) adjust the length of the lower leader so that it extends just a little past the lower arrow, but only on this dimension.

s

thx, -Bob

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