If it's a hydraulic clutch setup there is no adjustability. The only way you could change clutch pedal ratio would be to use a master cylinder with a larger bore or a slave with a smaller bore or both. It will increase the amount of effort it takes to depress the clutch pedal.
Or fab up a spacer of some type, that you can attach to the pedal to make it fatter in the direction towards your foot. Maybe even chop another clutch pedal to use in this project so you can still apply a clutch pedal pad to it.
Semi-long story, 100% related, still gives me a chuckle:
Years ago a friend of mine had a 3500HD wrecker with the NV4500. I'd never driven an HD before; my wrecker at the time was a 3500 with an automatic. He had a project truck he'd sold to someone out of state and offered to tow it to them for an extra cost. Long trip so I went along to drive on the return trip.
We drop the truck off, I jump in the wrecker, and practically clobbered my foot with the clutch pedal. I asked him WTF is going on? He had a 2x4 block attached to the top of the clutch pedal with big hose clamps. It's still not making sense to me, so I asked him why? The seat adjuster doesn't work and he couldn't push the pedal far enough. It's STILL not making sense, we're practically the same height! I made him get out of the truck and we stood next to each other and that's when I realized he had short legs and a long torso to make up for it.
I had to pull that block of wood off so I could make the long drive home. No way I could drive it with that in the way. I also teased him mercilessly every few hours along the way, and then of course at random times later.
Richard
