4.3 I think I found this company on the links page. They sent a free catalog to me about 2 days after I requested it.
www.classiccheveroletparts.com (405)631-4400 phone. I called them up about this part but couldn't get an answer to my satisfaction. they told me all of these trucks had the master cylinder mounted to the frame. I wanted to know how much fabrication would be needed to make it work with stock pedals, espeacially the clutch pedal.
