Pitman arm use has been discussed on first generation Camaros, and second follows the same discipline:
For instance the 227 casting # is for the fast ration (5.8 ") and is used for both power steering and manual. however the splined holes are different diameters. The manual steering box has a smaller shaft and PS has a larger shaft.
Here are good links explaining Pitman arm lengths and uses:
https://www.yenko.net/forum/showthre...ghlight=pitman
https://www.yenko.net/forum/showthre...ghlight=pitman