69 K/1500 steering box question

[Rob H.]

I just picked up what turned out to be a 69 GMC k/1500. It's rusty, abused and pieced together which makes it just perfect for what I'm doing. I had wanted to convert my one truck with a title to a 4x4 using the best parts from all of them. I had entertained using a 73-87 frame and cutting down to fit, but then found this 69. Now for my question, the steering box seems to be worn pretty badly. I can see the arm coming off the box is indexed differantly than the 2wd boxes I have on my 67 and 70 and 72 trucks. Just curious what junkyard steering boxes will work or if I can possibly use one of my 2wd boxes? My 67 has the hydralic ram power steering. Any help or advice will be greatly appreciated. Here's a pic of the 69 as it sets now.