The 1 pint should last you throughout the day as you drink water in-between. If you are used to the MC, then you will most likely get hungry with only this much oj. This fast is not as strict so just drink more oj if you feel hungry. It will slow you down, but it will also help extend the length of your fast since you will have more energy.
If you ask on this forum, people will tell you that as long as you are not eating the SAD, then you are already doing your body a great favor by fasting from that diet.