In the time it would take you to fulfill the requirements for another bachelors, you could already have earned at least a year (if not more) towards a masters degree in comp. sci. or ME. It is not unheard of to get a science bachelors in one field and then switch to something else for your graduate work. Worst case scenario, you would be registered as a masters student and have to take a handful of comp. sci. courses in order to get up to speed.