I also looked into the harbor frieght hoist and even the large gantry. Decided to build one myself with 2" ID iron pipe. It worked great with a 2 ton chain hoist. This will even lift the cab off the frame. Welded at stress points and left thread to take apart if needed.
See pics- http://good-times.webshots.com/photo/2758989080103567918qtfmwk