I know this has been beat to death, this is one of those things where you do a search and you get too many results, most off topic. I've got to replace my rag joint, again, and going to change to u joint. The best I can tell, the column shaft spline is 1 - 48 (.985), the steering gear is where I can't figure out what it is. To count ¼ of the threads is 9, best I can tell, X 4 would be 36. I get .773 to .796 depending on where I measure across the splines, not at the flat. The truck is a '76 Scottsdale, 2wd, power steering, not sure of box #, small block.