I don't see why not. I tend to go to extremes when I build something, so take this with a grain of salt. I would fab up a frame, and bolt/weld the old frame to it, and thus build an off road trailer underneath it. Depending on how wide it is origanally, I would either make the axle so the tire stick out ala M416 style, or build wheel wells underneath and use the space undneath the main tent box as storage for water and such. I love the old apache's and would get one if I had the coin. (I've spent too much time figuing on how to attach an apache box to the M416... it's a sickness really, and has no scientific or social value.)
That's my grandious idea, may help you, may not?
Mayne