I just put a new SB in my chevelle and changed the oil after the intitial breakin. During this time, the motor did get pretty flooded a couple of times. When I cahnged the oil, there was gas in it. The carb is a liitle rich right now too, what should I check or do to prevent this in the future?

Well i had the same problem with gas in the oil after i went to a place to get through emmissions on my 68, i later found out they had put a strip kit in my carb and somehow gas was getting in the oil and i gave it to a good friend of mine and fixed it he said they had put to big of jets in my carb.

Maybe thats it

If you were using a mechanical fuel pump the diaphragm may have ruptured which will also pump fuel in to the oil