Simple question, with a rather complex reply. "Power steering gear", covers a broad range of parts, required to do the conversion. Although not difficult, there are some subtle differences on the 4x4 trucks, compared to the power steeirng conversion on the 2wd trucks. Any Saginaw power steeirng pump & corresponding power steering pump mounting brackets & hoses, along with a '68-'86 GM Saginaw 605 power steering gear box, will get you well on your way. Here is a good link to the process: http://www.classicperform.com/power6066.htm
