This fits almost perfectly in my Squier CV 50s Stratocaster. Other than a tiny amount of the cavity being visible, this bridge drops in and secures via the original screw holes with no issues.
The bridge itself is quality - the tremolo is extremely responsive and the saddle design allows for low action and easy adjustment. It's worlds away from the stock vintage-style bridge.
The kit comes with everything you need to install this from scratch, including an adjustment key for the saddles.
Can't recommend this enough. This has transformed my strat!