Add Cisco 2960 to stack

I have a Cisco 2960 that I am wanting to add to an existing stack. The switch I want to add to the stack has already been configured to be a master in another IDF. I have to backfill this switch because we don't have time to wait for a new switch to arrive. My question is, can I just factory reset the switch that has already been configured and add it to the stack and label it the next switch in the stack like switch 4 or should I copy the config from another switch and load it in the switch in question? Thank you for your help!