1970 GM C 4X4 1/2 ton 6 bolt WITH 373 GEARING AND A EATON POSI ,3.73, 12 bolt posi, COMPLETE DIFF . and the complete front diff with disc brakes, ,the rear diff leaf springs. 58 3/4 inches backing plate to plate,center spring perch to perch is40.5 inches,backing plate to center of spring perch is 9 inches .OR BEST TRADE ON CHEV PARTS-BBC-SBC.