As to the CPSIA labels that also contain the FTC care and content label information, you are giving the gov. all the info they are asking for. They haven't said that you need 2 seperate labels or that you can combine them. I'd go with what you have. Remember they can kill you, but they won't eat you!!
I happen to use both, plus size labels, because mine are single sided, and I already have the CPSIA label printed, and I use woven FTC and size labels. I don't stack them, I put the CPSIA label above and sew the FTC and size labels to the bottom edge. Then I sew them as a unit on to the facing.
The bodysuits will just use your CPSIA label over the top of the existing labels. Don't remove the Child of MIne labels.