VBA - Retrieve data from ASP page - vba

Question

I originally created a VBA macro that would uses IE automation to click specific form buttons on an ASPX page. The page has 5 form options you have to pass through.
drop down list for group
drop down list for location
Graphical calendar where you select the date
List box for area's
Generate Report button
I would like to move away from using the IE automation to something more efficient. I have seen other posts where they were able to pull the data back using the MSXML object. This is what I was able to build from what I read but am not having any luck figuring out how to pass more than one of the form options. This is a company specific/internal website so unfortunately it is not available externally for me to be able to post the link example.
The element ID's are as follows; dlDivision, dlLocation, calRptDate, lbAreas, btnGenReport.
Public Sub XMLhttp_Search_Extract()
Dim URL As String
Dim XMLreq As Object
Dim POSTdata As String
Dim i As Integer
URL = "somewebURL.test.aspx"
POSTdata = "(" & Q("dlDivision") & ":" & Q("divisionNAMEHERE") & "," & Q("dlLocation") & ":" & Q("123 - Location") & ")"
Set XMLreq = CreateObject("MSXML2.XMLHTTP")
With XMLreq
.Open "POST", URL, False
.setRequestHeader "User-Agent", "Moilla/5.0 (Windows NT 5.1; rv:23.0) Gecko/20100101 Firefox/23.0"
.setRequestHeader "Referer", "somewebURL.test.aspx"
.setRequestHeader "Content-Type", "application/json; charset=utf-8"
.Send (POSTdata)
For i = 1 To Len(.responseText) Step 1023
MsgBox Mid(.responseText, i, i + 1023), _
Title:=i & " to " & Min(i + 1023 - 1, Len(.responseText)) & " of " & Len(.responseText)
Next i
End With
End Sub
Private Function Q(text As String) As String
Q = Chr(34) & text & Chr(34)
End Function
Private Function Min(n1 As Long, n2 As Long) As Long
Min = IIf(n1 < n2, n1, n2)
End Function