[Xist]

Cut the frame at roughly in the middle of the doors. Make pie cuts slightly ahead of the box in the upper and lower flanges of the frame(assuming it's a C channel). Pull the two sides together evenly. Plate, box, add a chunk of tubing, whatever, so you can mount a hitch.

Unplug the taillight wire from the firewall and install a flat-four plug on the factory wire and you got lights.

Go to local DMV and register as homebuilt trailer.

It will haul more than you're likely to ever put in it. A. The axle's not driving it anymore. B. You've lost the rear axle weight of the engine and whatnot, so gained that much hauling capacity.

DIY Trailer From Truck Bed--The Garage Journal
It seems like a cheap and easy way to make a great trailer