From the Side a hint of the hardware used. All 1/4x 20 thumb screws and wing nuts and 1/2"x 2" angle brackets. Note that the finder attaches directly to the bracket.
From the front a more revealing look. Some bending and tweaking took place. A couple of washers for fit were needed also. The post was made by a friend of mine on his lathe but a standard 1/4x 20 threaded sleeve would work.
Close up of the two angle brackets and washers from underneath the finder.
A view of the connection points and brackets. The top bracket is still at about 90 degrees. I bent the bottom one to allow clearance at the back because the tripod control arm was slightly in my way. I know that this looks home made, because it is, but it is a lot sturdier than the plastic adapter that came with my astronomy binoculars. That is what prompted me to make my own heavy duty adapter and then seeing the red dot finder addition made me have to try it too. 
A couple more pictures per request.
