Help passing files to another method...

I have a method where I am trying to pass a collection of one or more files to another method. 

I need help passing files to another method.  The method SendFiles_AWSS3 return aThree-dimensional array back to GetDocumentCollection.... Your help is greatly appreciated.

[System.Web.Http.HttpPost]public ActionResult GetDocumentCollection(FormCollection Form)
{            var Model = new DocumentMetaData(); if (Request.Files != null)  {      ArrayList DisplayFiles = new ArrayList();      for (int i = 0; i < Request.Files.Count; i++)      {          if (ModelState.IsValid)          {             HttpPostedFileBase GetFile = Request.Files[i];             DisplayFiles.Add(Model.FileName);          }     }             SendFiles_AWSS3(DisplayFiles);<-- how to pass the collection of files to method  }              // end upload file return RedirectToAction("ShowFiles", TempData["DisplayFiles"]);
}

must receive collection of one or more files.....

private ActionResult SendFiles_AWSS3(IEnumerable<HttpPostedFileBase> _GetFiles) <--- Getting an overload error message
{ 
   fileName .....
   FileID   .....
  return (Three-dimensional array array list) <--- Must return a Three-dimensional arraylist with file data...
}