Well I found a solution to my question. I took JSON data from my ajax call, ran it through a loop adding html tags to each element. I then assigned the innerHtml of my scrolling_list to that final array. See following:

Added this bit of javascript

var data = JSON.parse(xmlObject.response);
var finaldata = [];
for(i = 0; i < data.length; i++)
{
    finaldata.push("<option value="+data[i]+">"+data[i]+"</option>");
}
document.getElementsByName('SECOND_SELECTION')[0].innerHTML = finaldat
+a;
[download]