Your concern may be well-founded. I only used brass because that's what I had. It is, however, a soft metal and would sooner bend than to crack. However, perhaps a nice, thick, steel pipe, cut to the length I need, would work better. I'll put that on my to-do list.

The reason for the Ford Dana 60 is because that is what I found. The width seemed compatible and the 8-lug GMC wheels fit. The price was right, it only cost me $200. I bought it from a friend of mine.

The way I plan to convert to 4WD is this:
I have a Muncie SM465 transmission out of a tow truck. I intend to mate it with a married transfer case. I found a company that does this service when they rebuild it, but I don't remember the exact type of transfer case. I'll have to look at the old e-mail from them to tell you. The front driveshaft I plan to use is on the passenger side.
Then I plan to use a Dana 44 front axle with the same gears of course, 3.73. This will require rebuilding of the front suspension. Speedway Motors does sell components to convert to a wishbone suspension. This is probably the method I'll use.

Yes, I do have a picture online. I will send it to you from my cell phone. It's not a high quality picture, but it gives you a general picture. As you will see, my truck looks stock from the outside.