After the paint dried I positioned my mounted painting panel right on the front of the backing board with double-stick tape to hold it in place as I gently flipped it over to screw it on, from the back, with 5/8 inch wood screws. This was pretty tricky and I will have to experiment with an easier method. I then attached standard hanging wire hardware.
My finished painting is securely framed and it cost about 1/5 of even the wholesale price I would have paid for a frame this size. The painting "floats" in the frame and nothing touches the front of painting itself. It has no glass or matt because it is sealed with Golden Archival spray Varnish. I'm pretty happy with the results!