Power Steering Box 55-57 Chevy

Delphi 600 box for 1955-57 Cheva. 18mm DD input shaft, 12.7:1 ratio. 1-1/8" output shaft with 32 splines (4 master splines). M18x1.5 pressure side, M16x1.5 return. 1450 psi max pressure, 1100-1250 psi optimum pressure.