It's been a couple of years since car seats were in our coach, but as best I remember we used them as our home state (Florida) required them. Consider doing what ever your home state requires.
They sat in the most forward couch position or the dinette.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
The Avatar Is Many Times Around The USA
Nobody Knows Your Coach Like Somebody Who Owns One Just Like Yours