KPI JSON properties

Thanks for the reply v-eachen-msft . 

What I mistook for a KPI was actually a Card Element. I found I'm able to do quite a bit with that element when it comes to the fill, the outline, border, and such, but I haven't found the right property name for the text.  This is what I'm currently using: 

    "actionButton": {
            "*": {
                "visualHeader": [
                    {
                        "show": true
                    }
                ],
                "border": [
                    {
                        "show": false
                    }
                ],
                "buttonText": [
                    {
                        "$id": "default",
                        "transparency": 0,
                        "fontColor": { "solid": { "color": "#ff0000" } },
                        "Color": { "solid": { "color": "#ff0000" } },
                        "textColor": { "solid": { "color": "#ff0000" } }
                    }
                ],
                "fill": [
                    {
                        "show": true
                    },
                    {
                        "$id": "default",
                        "transparency": 0,
                        "fillColor": { "solid": { "color": "#66bc43" } }
                    },
                    {
                        "$id": "hover",
                        "transparency": 40,
                        "fillColor": { "solid": { "color": "#66bc43" } }
                    },
                    {
                        "$id": "selected",
                        "transparency": 20,
                        "fillColor": { "solid": { "color": "#66bc43" } }
                    }
                ],
                "outline":[
                    {
                        "show": false 
                    },
                    {
                        "$id": "default",
                        "lineColor": {"solid": {"color": "#000000"}},
                        "transparency": 0,
                        "weight": 0,
                        "roundEdge": 0
                    },
                    {
                        "$id": "hover",
                        "lineColor": {"solid": {"color": "#000000"}},
                        "transparency": 0,
                        "weight": 0,
                        "roundEdge": 0
                    },
                    {
                        "$id": "selected",
                        "lineColor": {"solid": {"color": "#000000"}},
                        "transparency": 0,
                        "weight": 0,
                        "roundEdge": 0
                    }

                ]

            }
        }

buttonText doesn't seem to be the right name, as you can see, I'm also flailing about trying different names for the color under there, but nothing so far has worked. Would you have any ideas on this one? 

Thanks!