steering box question

[76bonanza]

I got my truck aligned and it still pulls to the right. The guy at the shop showed me when you start the truck and the gear box pressurizes the wheel starts to turn to the right on its own. He said something to wrong with the gearbox. Does this sound correct also is there any adjustment that can be done or do I kneed a new box? Also anyway to id a power steering box? Dont think my 68 came with it I think someone pulled it from another year truck but dont know what year.

Thanks for any help.