68 Nova/Camaro power brake/ clutch pedal assembly

[jasonL78]

Looking for someone to verify on a 68 nova/camaro a return spring was used for the brake/clutch pedal assembly on power brake cars?? I was restoring my brake clutch pedal assembly from the 68 L79 and noticed from Gregs Nova research page that it was missing the brake pedal return spring. So I went and checked my 68 L78 Nova that also is an original power disk brake car and it also didn't have a return spring? From what I can see on the L78 the diaphram holds pressure against the pedal so no spring would be needed. Can I assume this is correct?

Picture #8 is what caught my eye maybe Greg can explain.

http://www.chevynova.org/1968ClutchPedals.html

Jason