How do you adjust the position of the pivot point?

I dropped a tank prefab into the hierarchy of a project I was working on and wrote the code for the locomotion.Everything was fine except the rotation! The rotation was off, I later figured out, because the pivot point was not centered on the tank. So I went to GameObject on the top of the window and selected the “Center on Children” option. However, the pivot point was still not centered on the tank. Is there a way to fix this??

@WorldWarAce

A bit more information on how your tank prefab is setup may help us come up with an answer for you. I can think of a few ways to fix this, but it would be dependent on the way your prefab is setup and the position of your locomotion script in the prefabs hierarchy.