Received mine yesterday, will have it installed "soon".
Actually much more soon than later coz I really REALLY miss having one of these on my new-to-me E350.
Ray's version is as good as ever, instructions almost insanely helpful, illustrations out the wazoo so installation should be easy even for those not used to doing such projects.
I'll swear this device is by far the most useful ever devised---congrats to John Winsteller and Ray aka 1der for these! If you don't already have one I only ask why?