Long story and not really relevant but I am being offered at good deal to go to the HR-20. I now have my dishes mounted on the 4X4s supporting a deck and am wondering what the foot print of the plate is, will it work on a single 4x4 or will I need to incorporate an addition surface to mount it on. Does anyone have the dimensions of the bolt pattern or perhaps a template? D's rep was not able to answer when the slim line dish would be available.