Doggone it Richard I'd like to do that, seriously.
But it seems there's more work here in Texas than I can get to.
We have heavy clay, stuff from, well, sounds like that anyway.
We've found the small screw in anchors from TSC work just fine, one on each open corner.
I snapped some pictures of it while it was up in the air for details if you need it.
In you situation I'd consider what I've done before. Same overall plan but instead of elbows at the corners for easy dragging. But on the closed end have open pipe that will take axle stubs. With your three point hay fork you lift up that end, slip in the stubs with wheels and tires, pin them in place, lower. And then go to the front, lift with hay fork, put a dog chain (short piece of chain for just holding things) in place to keep the shed in tow. Haul, but, no, shed. /forums/images/graemlins/grin.gif