It depends on your family. Our families tradition is 2 middle names and our children have just that (and for that matter their 1st and middle names are distant family names).
adding after market product to a car seat can interfere with the operation of the seat. Rolled up towels placed after buckling and properly trightening the harness are so much safer, as they do not go under baby or harness.
Have the seat inspected by a liscensed Child Passenger Safety Technician. To find one, or even ask you question with people who know, check out car-seat.org
Not all fire departments are TRAINED in installations and a CPST would have the best knowledge. There may even been a safety event near...