In drafting, place a dimension. With the dimension still highlighted select the third Icon, Break/Other. At the bottom select 'NOTE' then select the dimension, it will find the attach point. You can position the note afterwards.
In the NOTE command area, 4th from the bottom, select 'CALLOUT SYMBOL:' hold down the mouse button and select the symbol you want to use. Use the 'MOVE' command to reposition the symbol. DONE, DONE. Then EDIT the dimension and the CALLOUT symbol is associtive, it moves with the dimension.
Also look at the other commands, Special characters, FCS characters.
Hope this helps, Dan