Here's some pictures. Hope they are clear enough. It's raining so I didn't pull it out of the barn.
top left is the removable pin one on each side.
top right is a little hard to see. The bottom pipe is part of the sub frame. just above it is a shaft welded to the sub frame and the bottom of the loader arm has a curved area that sits on top of it.
lower left is a stand. It is pinned at the top and pivots at the bottom near the bucket.
lower right is a side view, showing the side sub frame with the sub frame pipe at the bottom, the support shaft, and the removable pin.
Doc is right about the concrete. a smooth level surface makes it much easier.
Instead of welding on the stands you might be able to set some 6x6's under it on each side. The trick is to have it steady at the correct level so you can drive under it and the bottom of the loader arms will slip into place.
Good luck!
Jim