Does anyone know of a way to use a macro to change the value of the cells in the design table?

For example... if I have a form where the user enters a value... say beam size... the macro will edit the cell of the design table that corresponds to the beam size and the design table can update the part.

My design tables are internal inside my solidworks part. What I'm having trouble with isn't the code to actually change the value of a cell, but how to access the cell that is inside the design table in the part so that I can change it.