Radiant heat - I love the idea.
I see no reason that it couldn't be done, but you would probably want to add some insulation below it, which requires raising the floor. That would require looking carefully at how that impacts everything - access, brake & gas pedal height, etc. You might choose to only install it in certain areas (bedroom, bath, etc.) where there will be a minimum of such problems.
Would it be electric or water? How will that fit in with your current heating system? The extra flexing in a MH as compared to a stable traditional building might cause early failure.
2008 Itasca Meridian 37H & 2015 Flagstaff T12RBST
2011 & 2012 Len & Pat's "One lap of America"
27K miles & 41 states in 13 months - Woo Woo
Yellowstone Lake 6-1-2012