steering box identification

[scott123]

bought a parts truck a couple of years ago. it was an 72 body on a 84 2wd chassis with spring hangers welded to the front to convert the 2wd frame to 4wd. a plate was welded to bolt the steering box (a pitiful try at bracing the box)...get the idea...i need a rag joint and have no idea whether the box is of a newer model or not...it has the splines with the flat spot..not notched for the bolt to go partially thru...the rag joint is shot but the box is OK...i can't find any numbers on the joint but can i ID the box by the casting numbers..year model...to find the right joint...any help will be greatly appreciated....s