Aliner / cruiseliner enthusiasts

I am quite impressed with the aliners, but dissapointed they do not come in a serious off-road format. To any aliner or cruiseliner enthusiasts, how strong are the bodies? I am contemplating building a chasis with independent suspension, trailing arms on air bags, and "attaching" the Aliner to this. Am i off with the faireys or do you reckon the body would take it. The few I have seen out and about were given a fair hiding over the gravel roads and seemed to handle it OK,
Any comments would be appreciated ...