She would have to get a Medical card, if you do that then your showing shes not disabled and able to work anytime, even if she went to get her physical, the new physicals with lifting and raising your arms overhead, toes to head etc, would she be able to pass that, Again if she does, your disability claim goes right out the window. I would use her as Navigator, Trip Planner, Log keeper, Mileage and routing, and leave the driving to you. Having a CO-Driver youll have to keep logs for both of you showing her status etc....Its not worth the risk or damage she might incur if she has nerve damage your going to need a real good air ride seat to prevent hurting her more, S/T dont ride like a cadillac even with Air Suspension, Air ride seats etc Its still a bumpy ride in parts of the country that take pride in presenting a Bumpy pot hole filled cow path and calling it an Interstate....I think you would be risking her disability and I wouldnt do it...My 2 Cents