My father in law wanted a rear weight since he doesn't have a backhoe. I had a few concrete blocks from a wall I cut off 2 years ago. I estimate it weighs around 500lbs. Only goof I made is that the 3ph attachement is too low. So I have to sit the block on something 1ft off the ground to be able to hook it up.
Here's a picture, unpainted, on my tractor
And here it is painted
Here's a picture, unpainted, on my tractor
And here it is painted