No need to weld, that picture was just grinding the excess u-bolt ends. Power inverter + grinder.
My buddy Dave found a used OEM spring pack at a local salvage yard on the www, called, had them take it off and prep it while another buddy drove him out of the park to go get it, new u-bolts and a new center pin. In the meantime I took the damaged pack off my truck and took it apart. When the OEM one arrived we took it apart, used its top leaf and rebuild my aftermarket pack. Put the rebuilt pack on the truck and away we went…
…it was as fun as it sounds…