gistfile1.js

//var formContainer = $("#ctl00_ContentPlaceHolder1_ffnpPayBrasPag1_dvBPCC");
var findPrev = function (node, needle) {
  var found = false;
  do {
    node = node.previousSibling;
    var nv = node.nodeValue;
    if (nv && nv.indexOf(needle) > -1) {
      found = true;
    }
  } while (!found);

  return node;
};

var addBrBefore = function (node) {
  var new_br = document.createElement("br");
  node.parentNode.insertBefore(new_br, node);
};

var form = document.getElementById("ctl00_ContentPlaceHolder1_ffnpPayBrasPag1_dvBPCC");
var h1 = form.childNodes[1];
var select = document.getElementById("ctl00_ContentPlaceHolder1_ffnpPayBrasPag1_ddParcelamento");
var label = findPrev(select, "Número de Parcelas");

addBrBefore(h1.nextSibling);
form.insertBefore(select, h1.nextSibling);
addBrBefore(h1.nextSibling);
form.insertBefore(label, h1.nextSibling);
addBrBefore(h1.nextSibling);