I have the same issue with my Ring Pro only it is on Hardie Plank siding. I installed it today because I needed it up and running. I used a door install wedge to plumb (or level) it. I can use your adapter if I make my own wedge.
What is involved with printing a L/H or R/H specific item that has multiple axis's. I don't know much about 3D printing but I know you can do anything with it.