Clutch linkage

Ok so here we go. I have a 65 valiant 6cyl and I want to run a 4spd I have already converted it to manual. So here are my questions 1. What it's the difference between 6cyl and v8 set up (from the pedal to the fork) 2. The difference hd and standard clutch of (again pedal to fork) 3. The two different rods lengths that go through the firewall

And I'm running a 73 3 spd flywheel to driveline