This manual steering box fits many GM applications from 1965-1991 and probably many more. It would accept either our universal pitman arm (7022940) or your stock GM (small style.)
Input shaft is 3/4"-30 spline. 6.25 turns lock to lock. 25 to 1 ratio. Stock specifications on this gear refer to it as 6 rounds lock to lock for a 24 to 1 ratio. Saginaw steering gear, as used in many GM vehicles.