the site cobalt sent u to has a lot of pictures and you may be confused as most of the pics are for under the floor; The assembly you need is for hanging on the firewall. Commonly called a swing pedal and there are plenty at that site but you may not recognize them.
So try to look for one that says swing or firewall mount.
Go to another car and take a look at how the pedal works.
It is a basic lever and fulcrum setup
You must have the proper parts to work together. Don't want those brakes to fail from a poor or wrong instalation. Luck