I've started to prototype a 4x5 camera using birch ply and the first generation of mounting hardware that I 3D printed.
Front and rear frames are finger jointed 6mm birch plywood. I'm not quite sure what I want to do for a lensboard. I may fit a small rabbetted frame to the front will allowance for felt and a 3 1/2" square board. I think that is reasonable. I will make the usual brass tabs to hold the boards in place.
If it's not clear I don't plan on having and tilt/shift movements in this prototype, focus may be on rack and gear in the front standard. the square protrision on the tube in the drawing is a stand in for a rack gear, but it might also be like that. and focus by nudging, at least for the prototype.
Currently I'm building two in ply and one in mahogany, though more consideration is needed to allow for wood movement in the mahogany. I haven't planned out the lensboard arraignment for that yet.
The bracket in the foreground was 3D printed, it still needs several post machining operations, including drilling and tapping for the mounting holes and tapping for the clamp screws. but I'm happy so far.