I put a factory 16:1 box in my Coronet a long time ago. Maybe back in the 90's? Made the car undrivable so I pulled that box out and sold it to a road race guy who put it in his Valiant. It was too hard to steer for him so down the road it went.
I ended up with a 20:1 box in my Coronet but it was still too stiff so I eventually yanked it out and switched to a Borgeson power steering box. Your mileage may vary.