Upgradable Turrets is a mod that allows turrets to be build and ungraded upon a turret base. There are currently three turret trees: the Machine gun, the Cannon, and the Radar. There will be many more when I both care and have time to make them. I would upload images and gifs but like the last required forum post for another mod I made I'm both not allowed and this post wont be vetted so wah wah.