What is the best way to attach a 2x4 rail between my fence posts? I was planning to cut the 2x4's between posts vs. running them through...just like the look better. Planning on a shadow-box fence 6' high. I've looked at fence brackets...but their an eye sore. Only thing I can come up is a toe-nail (using screws). This is a very cold climate so frost heave could be an issue. Thanks in advance.