I have not put on a custom turret from them, but what i have been told is that they come with instructions, and are very easy to do. They said it takes like 5 minutes.
The only thing I would reccomend, and it sounds like you are well on your way, is collecting range data for as far as you want to shoot with that custom turret. So if you want to be accurate with it out to 800 yards, collect your data to 800 yards. And remember that you will need to stay consistent with bullets, location, and temperature to get the most accuracy out of the turret.