Textbox input as file location for data merge

Sub MergeHorizontally() --Courtesy of Ron de Bruin
    Dim MyPath As String, FilesInPath As String
    Dim MyFiles() As String
    Dim SourceCcount As Long, FNum As Long
    Dim mybook As Workbook, BaseWks As Worksheet
    Dim sourceRange As Range, destrange As Range
    Dim Cnum As Long, CalcMode As Long

    ' Change this to the path\folder location of the files.
    MyPath = " File Location" 
    ' I would like for this location to be the path entered in a textbox on   Sheet1

Any ideas on how I can make this work? Thanks!