Thanks For the information Fang! There is a chance it's not poly but I did get two sprouts from it do far.
Gary, I agree with JF and would have chopped it down much lower. I would have brought it down to 2-3 ft, leaving no branches above the cut. This should stimulate vigorous new growth for you to work with once it has matured a little. Once the branches have matured, you simply select a few evenly spaced branches to graft. Once a graft takes, all you have to do is carefully monitor and remove any new growth from beneath the graft. By doing this, you will save yourself a lot of work later by not having to constantly remove the vigorous Manilla branches.
Simon