[dsraven]

I have used the old style chevy pedal on a few projects and find the arm can be bent as required or a new arm made to fit the need. as mentioned in other posts it is important to have some flooring or something to simulate the depth of the flooring you will use so the pedal travel can be fine tuned. if you find you don't have enough travel the arm can be made longer if you have room, shorter if you need less travel. you could also fab up an adjustable pedal arm so you can fine tune that to get it right and then make the final pedal arm from that pattern.
pedal placement on the floor and pedal height/angle is also important. otherwise you get a cramp in your leg/calf on longer trips. what I have done sometimes is mock up a wooden wedge to use as a gas pedal for mock up and then sit in the seat with my foot on the pedaland with a coffee. when the coffee is done you will kinda know if the comfort level in your leg will be ok.
make sure to check foot room for access to the brake pedal. also height in comparison to the brake so if you gotta hit the brakes in a hurry to avoid collision it will be easy and no need to lift your foot a lot.
I drove in one vehicle where I found the drivers ( clutch) foot seemed to work it's way under the brake pedal. that was a surprise when I needed the brakes.