Returning FieldFrame checkbox fields in a non-list format

I’m using a FF Checkbox field to gather some of my data. When I return it, it automatically returns like this:

<ul>
<li>item 1</li>
<li>item 2</li>
<li>item 3</li>
</ul>

I need the data like this because it is going into a JSON format:

"item 1", "item 2", "item 3"

Is there any way to achieve this?

thanks brian