I was thinking about getting a fiber optic front sight on my Kadet so that I can have the same sight picture that I like on my P-01 (fiber optic front, blacked out rear). When I go the Dawson Precision website, there are 6 different heights. Does anyone know which height will work with the stock rear sight for a combat hold? I tried looking this up, but my Google skills resulted in multiple different answers, and none explained their sight picture.

Bueller?

Try the Dawson sight calculator.

The sight calculator requires you have the sight measurement, so it wouldn't have been helpful.

I ended up just borrowing a friend's micrometer. My measurements came out to 7mm or .276 inches total sight height, 5.15mm or .202 inches above the slide.