It can be done!  Dig the reservoir and tamp down the cascade area.  Chisel out the waterfalls just like a staircase.  Lay down the underlayment, install the liner.  Set in the Bio fall filter and Skimmer unit, hook up the pump and your ready to rock and roll….literally, start to move the rock in right away to level out all the filter units.  Build your cascades, foam in the rocks, fill the pond and turn it on.  Now sit back and enjoy.