I have an early 30-U that has the dampening springs. It had no shocks but I eventually added shocks and retained the dampening springs. The early 30-U seems to retain some U features like the dampening springs, vacuum tank and thermosyphon cooling. In addition to the shocks, the shock linkage and the axle mounting plates there are also re enforcing plates that go on the opposite side of the frame where the mounting bolts for the shocks are located. I may have some extra parts in my storage unit if you need them.