Figure out what they go to and see how they were mounted. All of the weight isn't borne by the angle iron (it could also be a casting) but by pivoting against the bottom of the weight bracket and mostly just retained by the angle iron (or casting). See what the weights were on by searching "tractor weights in Texas" and comparing pics. There is a company there that sells knock off weights and has pictures of most weights. After you find out what they are off of, search the net for pics of weights on that model tractor and the mounting will be displayed. It's OK to hang from angle iron if they can also rest against something.
After a quick check, I'm not sure what they are off. The might be New Holland but might be a mongrel.