Distance between plates

Can you give me two dimensions?

What distance do you need between the front and back plate to accommodate those hinges?

What is the radius (or diameter) of the hoop?

If anyone wants to play around with the 3D model assembled to the best of my knowledge, here is a link to it in OnShape. The link should take you directly to the assembly online, no account needed. https://cad.onshape.com/documents/92a27130565ccbdd6001f9f8/w/7aa86f355a230e87c3ca175f/e/c167f4a07f5db41e9de2e3e1

If you want a dimension, for example, click on two parallel surfaces and it will display a distance in the bottom right corner.

(This is an old link forwarded from another post, so let me know if it still works for you.)