rearend u-bolt clamp , what do they come on

[homemade87]

I am going to build me a set of traction bars for my 82 and seen this picture with the lower u-bolt clamp with the nuts on bottom. I have mostly fooled with 80's trucks and have not seen this bracket. Mine has a u-bolt with the nuts on top and no lower bracket , u-bolts just go around the axle tube .I would like to have a couple of them to weld to for my traction bars but I don't know what they come on. If any one has seen and know what years and size trucks they come on I would appreciate the info so I can start looking in the junk yard.

This is a picture I found of what I am talking about.