throttle lever arm length

[Bob Haskell <rchaskell@earthlink.net>]

For a tri-carb, the lever arm that attaches to the accelerator pedal where it 
sticks through the foot well:

I have one that's 1 5/8 inches long (shaft center line to ball joint center 
line) and another that's 2 1/4 inches.  Either one the correct part?

Bob