Just purchase an iMac. During setup it told me to power on the magic keyboard and magic mouse. I did, and set up my iMac. I'd like to sell both now (magic keyboard and magic mouse). I have a wired Apple keyboard that I prefer and also a magic trackpad. If I ever need to setup this iMac again can I do so with those instead? Will I need to unpair the trackpad to my iMac before setting up my iMac again? Because during my iMac setup I tried to use my magic trackpad that I was using with my Mac Mini previous and it wouldn't connect.