Well, I have been wanting to do this for a while now, I have a old skid steer bucket, it was converted to fit on the loader of a IH 460 farm tractor and I just reconverted it to 3-pt. I had to put on a aux valve and a cylinder for a top link so I could dump. The cylinder is WAY to big and I'm going to use a smaller cylinder and put adjustment on it with swivel ends (like a top link should have), But that will half to wait till I find the time.
I can haul about 4X the amount of manure to the garden in 1 trip, I have hauled around 5 loads so far and it seems to work great!
The 3-pt picks it up with ease, I was worried that it wouldn't be able to lift a full load but I haven't had any trouble. This is only going to be used for light materials, I don't want to damage my tractor.
The valve that I put on is a 2 spool valve, I'm going to run another aux to the front of the loader, then I'm going to build a grapple and then a 4-in-1 bucket.