They're about as scarce as a chicken with lips. Most of them got scavenged up by us round track racers in the mid-1980's. We ran 3/4 ton Chevy rear ends with 4.10's on 1/4 mile dirt tracks, with a Muncie 4 speed locked into 2nd. gear. The 1.88:1 2nd. gear gave us a 7.70:1 final drive ratio, perfect for a "long" 1/4 mile track measured around the infield. The "short" tracks were 1/4 mile measured around the outside, and we used the 4.56 gears at those tracks. Some guys tried running the Muncie transmission in 3rd. gear on the longer tracks with the 4.56, but then the transmission cases would split wide open from the torque load. Dirt track racing puts an unbelievable amount of load on driveline components.
Jerry
