The only thing I know is on my 49' is you have to get the one with a round hole on the back. I ordered a replacement pedal not knowing that I had to have one that was for a 49'. There's a difference in them. Hope this helps. The one that I have has a built up rubber on the back for rod that comes through the firewall and it has a press type fit to keep it in place.

1949 Chevy 1/2-Ton ~ Red Truck

In the Stovebolt Gallery
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