Ok, here’s one for $60 that’s good to .0005” resolution. I spent like 2 mins looking. You’re right on the $20 one - doesn’t have the resolution. I hastily posted the gauge I liked best visually without reading its specs.
The end float range on the crank is .004” and the range on the transmission is .008”. $60 height gauge is overkill and will do both.
iGaging Digital Electronic Height Gauge with Magnetic Base, 6 Inch
https://www.amazon.com/dp/B0026MTCG8/
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