Gunpilot, thanks. If your DJ-3A body is on an early (pre-'70) CJ chassis you won't be able to use the DJ fuel tank. The early CJ chassis has a V-member at the rear of the frame to give extra strength to the drawbar. The DJ frame doesn't have this, which allows the rear fuel tank to fit. I've attached the best photo I have of my tank, taken during the original frame off. The tank is only 12 gallons, I'd like to fit something larger in mine.
My steering setup draws heavily from both the Saginaw conversion that is (or was) sold by Advance Adapters, and the later model CJ power steering. From the steering column to the box is Saginaw conversion, but the box mount is a modified CJ-7 bracket that I sectioned so the box would mount closer to the frame. The plate between the frame rails in front of the grille is part of the box mount also, it is 1/4" steel. This plate will also make a good winch mount if I ever put one on. Since the stock Jeep power steering box mount is known to flex and crack when off road with big tires, I installed an aftermarket brace that clamps around the box and attaches to the opposite side of the frame. I had to shorten this brace to make it fit. I took a photo tonight out in the garage which shows all this, although probably not very well. The main reason I didn't just buy the Advance kit was cost; at the time (mid-'90's) the kit cost about $550 less the box and pump, I had about $200 in what I did for the same parts.
As far as the brakes, operationally there is nothing wrong with the drums, they work great, I'm happy with mine. But ...., drum brakes are terrible when they get wet, and one big puddle and you go from great to terrible in a heart beat. And if you run through any mud there are lots more places for the mud to get into on a drum. Maintenance wise there is no comparison, the disc brakes are much easier to service; the pads are much easier to replace than brake drum linings, and there are far fewer parts on disc brakes than drums. There is a reason why all new cars have disc brakes. Doing a disc brake conversion is not on the top of my list of things to do, but if I come aross the parts cheap enough I would probably do it.
I've attached a couple pictures here. If you would like to see more PM me with your email adrress.