I got the remaining bracket tacked on to the bike frame so it's a roller now! I sat on the bike and leaned a bit to see how it felt and it's pretty easy to lift the side car wheel. The frame is set up pretty neutral now. I might need to have the bike lean inward toward the chair a bit more. That should be easy enough done with the knee braces/support rods being threaded both left and right handed - loosen the jam nuts and twist them in or out. If they don't give me what I need that way I'll machine up a couple of wedge shaped washers to put behind the lower mounts to facilitate the bike leaning inward. I don't think that will be necessary, however.
Next up is to mount the windscreen. I've got a piece of flatstock cut and ready to bend. I'm going to get it bent to the desired shape to fit the windscreen and then I'm going to have to put a little angle on the top edge to accommodate the angle of the screen where it will bolt up. I can cut the tread plate for the floor now and I'll keep thinking about the handholds/grabrails and the fender design.