Andrew Kroger, Reddit:

It’s done! Following up on a recent post that I made on this sub, my iPad/Macbook hybrid is complete. The method involved defusing the broken LCD screen and backlight from the upper portion of the MacBook’s clamshell, modifying the retina display driver, attaching a magnetic iPad case in-place of the retina display and putting everything back together. In regards to software, I’m using Catalina’s ’Sidecar’ to wirelessly (bluetooth) mirror the once-existent Retina display and ‘keyboard maestro’ to establish the initial connection to the iPad upon booting up.

And here’s the results. Just great!