Your best approach would be to use the Origin Tool, select the 'Point Constructor' option, then using the full Point Dialog (the last item on the drop-down list of 'Origin Locations') use the Rectangular Offset option to position your note relative to some selected point, say an End Point, Mid-Point, Arc Center, etc.
John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA