I notched the plate and the 4X4 3/8 thick angle iron so could weld both sides.(that first pic on the last post i think you can see the welds) After welding the plate to the angle iron i took a section of pipe and welded it to the plate and the angle iron. Then boxed the angle with a second 4X4 again full welds around the pipe and along all edges.Used 1/2 in plate and drill press to fab my plates for the pins and full pen welded them inplace.i am lucky i have a shop to work in that lets me use the big miller 250 wirefeed welders any time i want.