Step 15: Saddle...
The saddle height should be approximately 3/8 inches above the soundboard. Shim under the bolt to get a height near 3/8 inches.
Note: This will result in high action, which is not typical for a ukulele, but with the imperfection of the fingerboard and frets, the higher action will result in a cleaner, less buzzy sound.
Once you get your height set, glue the stackup together including the bolt. Make sure the bolt is pressed up against the stop.