[skidmarks]

Mount one shoe to the backing plate. Hook the return spring into the other shoe then use you hands pulling on the second shoe to wrestle it into place. Then install the crossbar at the bottom to hold both shoes.

You can do it also with return spring pliers. The spiked end i used a small piece of wood so it didnt dig into the bonded shoes.
Rivited shoes you can use thw spike in the rivit hole

Either way works, i usually just do it the first way by hand