I've got overload springs on my 1/2 ton. There are brackets and u-bolt the hold the springs to the axel (aka perches) and on the end of the springs there are rubber pieces that contact the frame when it lowers down and contacts the springs when there is a heavy load.

Now that you guys are talking, I'm wondering if I'm missing brackets on my frame?

'51 Chevy 1/2 ton w/'62 261, HEI, offy, fentons, dual carter/webbers, t-5 & 12 bolt posi