I am trying to keep my truck pretty close to stock. The master cylinder on the truck now is an oval one with the plug that screws into it. All the ones I am seeing on various websites show the round one with the big cap. Which one is stock? Is there a mid year change on master cylinders, or has someone put an older one on this truck.

Thanks

 

Both of my 66 F100's have the round M/C. Have not seen a oval one on these truck myself.

 

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