In your book there should be a list of "Foods to Enjoy" and "Foods to Avoid" which give an indication of amount to eat as well. Eg Whole wheat pasta 30g. Brown rice 55g.
There should also be a list of sample meal plans for P1&2 which indicate the amount of food. It's not necessary to stick to the plans, they're just examples of meals and amounts.
The Good Fats Good Carbs book is also really good for indicating what foods to eat and to avoid.
Basically my SB diet is low carb, high veg and protein. I only eat a couple of carbs a day. It doesn't sound too dissimilar to red days to be honest.
I guess the whole philosophy of SB is a healthy, balanced diet.
Yes, coming from CD I would skip P1, you don't need it.
Normall moving into P2 from P1 you tend to phase in the carbs.... I honestly do not know to go about coming from CD. I'm guess you'd be ok to start in full blown P2.
If for some reason the Foods to Enjoy list isn't in your book, and you do opt for South Beach when you finish CD, let me know and I'll type it out for you and PM it or something.
~Silence~