Code to Increment Text Box Margin

[JFme]

I have very frequent need to change the top margin of the text block of shapes.  Each such change, however, requires multiple mouse clicks (select shape, right click Format/Text/Text Block/Margins).  Would like code that I can install behind a button so that I can select a shape(s), then for each click of the button the top margin of the text block of that selected shape(s) increments by +2 pt. (I would also have another button which increments by -2 pt.).  For example, if the top margin of a selected shape is 12 pt., multiple clicks of the button would increment 12 --> 14 --> 16 --> etc.  This would save me lots of time and reduce wear and tear on my hands!  Thanks very much for any help.