What is the problem to buy used gyro horizon and disassemble it to find out pendulum correctors or gyroscope fly-wheel in pendulum case, f.e.? Seriously, does selling used avionics prohibited in US today? Or you have no aviation garbage scrap-yards to find old gyro for free to look what's inside?

Why all flat-earthers are absolutely unable to do anything except copy-pasting dumb links and phrases? Even can't find a drawing of aviation horizon to find out parts that have to be added to gyroscope inside with only purpose to account Earth curvature. Really, flat-earthers who pose themselves as "critical thinkers" is the most incurious characters I ever met. I never saw a single flat-earther who posted his own thoughts, observations and replicateable experiment results. No one who did something himself. Only copypasting of stupid youtube videos made by swindlers for views, likes and ads money.

You could even remove correctors from gyro and just sit and watch how gyro without correctors will slowly change its slope according to Earth curvature and rotation.