This is a very hard question to answer. First of all each state has different standards. Also, I have not found any state that specifically addresses motor homes.
I did find a couple of web sites that might be of value.
National Highway Traffic Safety Administration: http://www.nhtsa.gov/cps/cpsfitting/index.cfm
This site provides a list of Child Car Seat Inspection Station by state or ZIP code. A phone call to some of these locations may give you some insight.
Governors Highway Safety Association: http://www.ghsa.org/html/stateinfo/laws/childsafety_laws.html
This site provides a summary of Child Car Seat requirements by state and access to state specific web sites.
I contacted Oakland County Health Division-Health Ed. in Michigan which was on the NHTSA web site and they were very willing to help but had little to add above contact the motor home manufacture.
I would think the first step would be to contact Kermit and see what his position is on the subject and then follow up with some of these or other sites.