I have been making a gun in Blender and I have come across an issue. Somehow one of my meshes got misaligned from the other. If you dont know what Im saying, here's a pic:

(soz for heavy image)
I wanna know if there is a uniform way to line up the corner of a mesh to another. Please help, this model took a very long time to make and I will be eternally grateful to the person who helps me.( Id give credit in the release but im not releasing this addon so meh. ) Anyways, please help! :(