In a training the other day the question was asked how to delete crews in the estimate setup. You can delete any resource as long as it is not in the estimate. In the Crew Setup there is an option tab that is very handy for lets say copying a crew to a new code or it will bring you to the screen to delete crews. One way to get to this screen is the following:

Then if you want to delete crews in the setup for example click on the delete crews tab. Also there is an option to delete the crew also in the Activity Codebook.