Steering Box Ratios

My 85 F150 has a steering ratio of 17:1.
I'd like to quicken it up to use a smaller steering wheel. What Ford steering boxes will interchange w/ the one I have now?
I heard somewhere that a "lighting" had a different pitman arm that quickened that model up, but I find the same (pitman arm)replacement part numbers for the F150 and the lighting, and the same with the steering boxes.
What's a fatso to do?

Thanks,
Meaux