For those of you who need an idea of how to move your LARGE shacks!:
My shack is 8x8 and even though you always try to build them light, they turn out heavy no matter what. I wanted to use my 4x8 trailer but there is a problem. On most trailers the wheels stick up above the floor so I could only fit something 4 ft wide on it. So what I did was take 2x10s and attach them to the floor. Make sure it's supported laterally.
The ends are angled, so when it comes time to load, I tilt my trailer down and it makes a great ramp. A winch/comealong on the front of the trailer hooks up to the shack.
Red=original trailer
Yellow=wood ramps (I used 2x10s)
Green=winch