any car seat will fit back there, i put two cars seats in the back.
i use the seatbelt and the carseats' belt that goes to the back of the seat- hooking it in the D ring on the trunk floor, there is one for each carseat.
of courese this is just for short trips around town. if the carseat did not have that belt in the back i would not do it, the cars' seat belt alone does not keep the carseat stable.
the kids feet might be cramed depending on the carseat