Will this credit rule still in affect if I am paying my credit card fully each month?

I don't believe it is seen as a debt load if you pay off the balance of your monthly bill, just the fact that you were not charged any interest on it is a strong indication that it is not seen as a loan at that point.

One discussion of car loan qualification mentioned that a B rating might include a credit card balance under 50% while an A rating would hav a balance under 33%.

No, your score won't be impacted by using 70% and paying off in full. Balances are reported to the credit agencies several days after the payment due date. As long as your payment is posted to your account on or before the payment due date, it will be recorded as an on-time payment. Your score will not be affected.

Creditors only report your utilization (balance) and payment history to the credit bureaus once a month, if that - it's not a "real time" system. If you pay in full each month, you're utilization rate is zero.

Yes, the rule is still in effect. If your balance is over 30% of your limit on whatever day they pick for reporting information, then it will hurt your credit score.

if you don't carry a balance, your credit utilization is zero.

no you will be fine