I LOVE this vehicle!! I don't know your children's sizes, but I have found that the
Chicco KeyFit and the Baby Trend Flex Loc tend to fit smaller babies.
Another idea, if you choose to not return the Snugrides, you can install the seats without the base (though I don't recommend this b/c there is a larger chance of you not getting it in at the right angle) and it may give you a little more room.
I totally agree with Susan. Seek out a carseat tech in your area
https://ssl13.cyzap.net/dzapps/dbzap...AFEKIDSCERTSQL. They will be able to help you out better!!!
congratulations on your 2 new babies!