A body big block power steering gearbox

Power steering was an option at certain times in the big block a-bodies, but I'm not sure why. The steering gear location should be the same for all a-body k-members. We have installed power steering in one '67 Barracuda with a 383 on a Direct Connection k-member. I will be doing the same with my '67 Barracuda convertible with a 440.