One way you could build it would be to Jet in your pilings by taking a 2" gas water pump a connecting a 1" steel pipe on the discharge side of the pump. Stand your wood pilings up where you want them and use the pump to wash a hole for the post to go into. I have done it a couple of times here on Lake Livingston. It works well and is pretty easy to do. You may have to get wet doing it though.
