External transfer into Cockrell School of Engineering

What I would like to know is how hard is it exactly to externally transfer into engineering at Cockrell? If anyone that external transfer from another university or through the CAP program ( I know acceptance isn’t guaranteed ) can tell me their experience (getting high grades, extracurriculars, admissions process, etc.). Also I read that certain departments of engineering are easier to get accepted to because they have more space available,so which department would be easiest to go into? I was thinking electrical or mechanical, but if you guys could add your input and possibly rank the departments from easiest to hardest to get into that would be much appreciated.