Copied the stock follower as much as possible while simplifying it. Should work without much adjustments (if any). Print with what will be the top of the follower (where the cartridges touch) flat on the build plate.
If you install it, and the front seems to be trying to tilt out of the magazine, pop the floor plate off and flip the magazine spring over.
You also lose last round hold open and the thumb pin. I've got some ideas on how I could possibly make last round hold open work, but it's so far proving to be rather impractical.
Make sure you orient the top down all the way, or it probably won't print well.