Transferring from IS to CIT

Hi, I am going to be a freshman this fall at CMU and I will be majoring in Information Systems as well as playing on the varsity soccer team. I picked Info Systems as a major because it is interdisciplinary and because it sounds very interesting, but it is kind of a leap of faith, because I’m not really sure exactly what to expect. I’ve always been interested in studying engineering, so if IS doesn’t work out, I want to have the option to switch into CIT. I know I’d have to take an intro to engineering course to do this, and I want to take one freshmen year so I have the ability to switch after spring break if I want to. My question is, what intro to eng courses are easiest to get a seat in if you’re not a CIT student freshmen year? And if I explain my situation to the appropriate professors and counselors when I am making my schedule, will they be supportive in putting me into an intro class?
Thanks!