If yes, how to do it, where to find the information?
Yes, you can take 6 units a semester (for the same tuition rate, above that costs extra, except for certain classes), but to do so requires dean approval. There is a form that you get from the registrar called the registration special approval form. You must get the form signed by your dean (based on your home college: jepson, business, or in the case of arts and sciences, your residential dean, which is westhampton for women, and richmond for men), and return it to the registrar.