OK, this one is baffling me.  I looked online and can only find reference to using smart dimension to dimension to a linear entity midpoint (by right clicking and selecting midpoint).  How can I get smart dimension to dimension from a linear edge to an ARC midpoint (OR center of arc for that matter)?  It seems to wanna only pick the nearest ENDPOINT of the arc (tangent to line).  See attached screenshot?  Must be something easy I'm missing lol.  Thanks!

Dave