How to change the font on a pivot side label using javascript

I need to dynamically add/remove sidelabels on a pivot and format the added labels. I cann add/remove labels but cannot figure out how to format them.

This should be simple, but I cannot not find anything in the docs that give a hinat as how to do this. I have tried ActiveDocument.Sections["pivot name"].SideLabels["label name"].Bold

I have tried ActiveDocument.Sections["pivot name"].SideLabels["label name"].Font.Bold

and on an on, but nothing works. Please help!